Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012

Contents lists available at ScienceDirect

Renewable and Sustainable Energy Reviews

journal homepage: www.elsevier.com/locate/rser

Electric vehicle battery technologies: From present state

to future systems
Sergio Manzetti a,b,n, Florin Mariasiu c
a
Fjordforsk A.S., Institute for Science and Technology, Energy Sciences, Midtun, 6894 Vangsnes, Norway
b
Uppsala Center for Computational Chemistry, Science for Life Laboratory, Department for Cell and Molecular Biology, University of Uppsala, Box 596,
751 24 Uppsala, Sweden
c
Automotive Engineering & Transports Department, Technical University of Cluj-Napoca, Bdul Muncii, 103-105 Cluj-Napoca (Clausenburg), Romania

art ic l e i nf o a b s t r a c t

Article history: Electric and hybrid vehicles are associated with green technologies and a reduction in greenhouse
Received 17 February 2015 emissions due to their low emissions of greenhouse gases and fuel-economic benefits over gasoline and
Received in revised form diesel vehicles. Recent analyses show nevertheless that electric vehicles contribute to the increase in
5 June 2015
greenhouse emissions through their excessive need for power sources, particularly in countries with
Accepted 6 July 2015
limited availability of renewable energy sources, and result in a net contribution and increase in
greenhouse emissions across the European continent. The chemical and electronic components of car
Keywords: batteries and their waste management require also a major investment and development of recycling
Life-cycle technologies, to limit the dispersion of electric waste materials in the environment. With an increase in
Electric batteries
fabrication and consumption of battery technologies and multiplied production of electric vehicles
Electric vehicles
worldwide in recent years, a full review of the cradle-to-grave characteristics of the battery units in
Portable energy
Green chemistry electric vehicles and hybrid cars is important. The inherent materials and chemicals for production and
Future systems the resulting effect on waste-management policies across the European Union are therefore reported
here for the scope of updating legislations in context with the rapidly growing sales of electric and
hybrid vehicles across the continent. This study provides a cradle-to-grave analysis of the emerging
technologies in the transport sector, with an assessment of green chemistries as novel green energy
sources for the electric vehicle and microelectronics portable energy landscape. Additionally, this work
envisions and surveys the future development of biological systems for energy production, in the view of
biobatteries. This work is of critical importance to legislative groups in the European Union for
evaluating the life-cycle impact of electric and hybrid vehicle batteries on the environment and for
establishing new legislations in context with waste handling of electric and hybrid vehicles and sustain
new innovations in the field of sustainable portable energy.
& 2015 Elsevier Ltd. All rights reserved.

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1004
2. Battery for EVs – state of technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1005
3. Life Cycle Assessment approaches on electric vehicles and batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1006
4. Green chemistry for novel battery technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1008
4.1. Organic compounds for novel battery technologies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1008
4.2. Enzyme systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1010
5. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1011
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1011

n
Corresponding author at: Fjordforsk A.S. Institute for Science and Technology, Energy Sciences, Midtun, 6894 Vangsnes, Norway.
E-mail address: sergio.manzetti@fjordforsk.no (S. Manzetti).
URL: http://www.fjordforsk.no (S. Manzetti).

http://dx.doi.org/10.1016/j.rser.2015.07.010
1364-0321/& 2015 Elsevier Ltd. All rights reserved.
 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012 1005

1. Introduction
High production costs.

Reduced overall size (compared to vehicles equipped with ICE).
Battery electric vehicles (BEV) are becoming increasingly inte-
Limited autonomy and top speed.
grated in several cities across Europe and the US [1,2], as a result of
Large recharging times or the need for special charging places.
the legislative measures implemented to reduce traffic pollution
The lack of electric motor noise can cause traffic accidents
and limit greenhouse gas emissions [3]. Since the advent of the (persons with hearing disabilities, pedestrians, cyclists, etc.).
industrial revolution, the environmental stress caused by fossil
fuel combustion [4] from the automotive and industrial park has Currently there are two constructive types of BEV, widely
increased to such as extent that oceans are experiencing a decline accepted by most companies in the automotive industry, according
in pH value [5], crustaceans and several species across the globe to the mode of transmission of the electric power developed by
risk extinction [6], and polar regions and ice-shelves across the the electric motor to the drive wheel:
world are overall experiencing a decline in total volume [7,8].
Albeit this critical state, the implementation of BEV has progressed
The electric motor replaces the classic internal combustion
more slowly compared to the pace of the BEV-technology devel- engine. The power produced by the electric motor is trans-
opment, due to legislative and bureaucratic processes and also mitted to the wheels via transmission (gearbox) (Fig. 1a).
given a series of complications for implementing these more
Each drive wheel is fitted with an electric motor (hub motor)
environmental friendly solutions in the society [9]. Such complica- (Fig. 1b).
tions are for instance a lack of a proper availability of recharging
stations, inexistent uniformity in adapters for different car-types Fig. 1 shows that the manufacturing solutions are similar in
and high custom-costs for import and implementation of vehicles that the size and location of the battery are the same. The use of a
in the European markets compared to the environmental benefits central electric motor design offers the advantage of using the
BEV pose [10]. same design as existing vehicles on the market. Also using the
BEV technologies are however missing a proper and full gearbox increases the efficiency of the usage of the power
recycling framework in several countries, and the usage of BEV developed by the electric motor depending on load being placed
and general electric equipments causes altogether still a consider- on the vehicle based on traffic conditions. However, it should be
able energy consumption which in turn results in increased CO2 mentioned that the use of a gearbox lowers the overall efficiency
emissions, particularly in countries without renewable energy due to inherent friction in the mechanisms that compose it.
resources [11]. BEV represent also a class of consumer items which The reduction of these mechanical losses can be achieved by
generate a considerable amount of toxic waste, given emerging using a periphery hub motor construction type for electric vehi-
and more advanced powering systems for automotive vehicles. cles, but in the lack of a gearbox, this solution can be used mainly
Therefore, in order to meet an eventual scenario of extensively for lightweight vehicles whose transport capacity is also small (e.g.
used BEV through the society, an assessment of the types of small vehicles for 2 passengers). In any of the above cases, if the
available battery technologies is critical, as many of these are construction of the electric vehicle makes use of the regenerative
based on nickel and cadmium metals, which are considerably toxic braking technology, this will lead to substantial improvements in
and an increased amount of battery-driven vehicles can affect the the energy efficiency of the electric vehicle [13,14]. The election of
environment if proper recycling strategies are absent. In order to a proper drive and optimal control strategy of electric vehicles are
survey this, an initial state of the art of BEV technologies is the major factors to optimize energy management to extend the
introduced, followed by a review of applied battery technologies, running distance per battery charge [15]. A number of battery's
and their recycling scheme. Finally, a survey of emerging green manufacturing technologies are suitable to equip an electric
energy sources with applicability on BEV is included along with vehicle, technologies that today, are widely accepted by the
elementary chemical descriptions of their properties, ultimately companies in the manufacturing industry:
followed by the concept of biobatteries, systems relying on biolo-
gical components for the generation of low electric currents.

2. Battery for EVs – state of technology

Battery electric vehicles (BEV) have an internal source of energy

– an electric motor powered by electric batteries located in the
vehicle. The powertrain gives BEV's the possibility to operate with
zero emissions in the place of use. Many of the manufactured
solutions adopted to build BEVs also make use of an “energy
recovery” technology that allows the electric motor to be used
both as a propulsion source and as a generator when braking or
when the vehicle moves freely under the action of gravity. This has
an important effect in increasing the overall energy efficiency of
the electric vehicle.
The advantages of using a BEV in traffic are the high torque of
the electric motor that is transmitted to the wheels and the
smoother acceleration (and deceleration) compared to vehicles
with internal combustion engines (ICE – Internal Combustion
Engine). BEVs also do not emit noise while operating the electric
motor and they don't produce pollutant emissions [12]. The
aspects make BEVs the ideal vehicles to be used in cities and / or Fig. 1. Constructive types of 2WD (wheel drive) battery electric vehicles (a-with a
urban areas. But besides the above advantages, there are some single electric motor; b-with hub motors; B-battery, EC – electronic control, EM-
disadvantages to using BEVs: electric motor, T-transmission, FD-differential, HB-hub motor).
1006 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012

Lead acid (Pb-acid) – batteries are the oldest type of batteries

used worldwide. They have the major disadvantages associated
with handling acid substances, the presence of lead in their
construction, a low stored energy/weight ratio and low stored
energy/volume ratio. Because of their inexpensive manufactur-
ing technology and a high ratio electric power/weight ratio
they are a cheap solution to equip electric vehicles.

Nickel-Cadmium (NiCd) – of all batteries they have the highest
lifespan expressed through the number of cycles of charge and
discharge (about 1500 cycles). Their biggest disadvantage is the
use of a heavy metal (Cadmium) in the construction, with
harmful effects on the environment and human and animal
health. EU directives limit the use of this type of battery [16].

Nickel-Metal-Hydride (NiMH) – NiMH battery manufacturing
technology and operation resembles that of NiCd battery. The
main advantage of NiMH batteries is the lack of memory effect,
Fig. 2. The type of battery and energy density efficiency (weight/volume).
which affects the maximum load capacity of the battery.
Compared to the Li-ion, NiMH batteries have lower energy
storage capacity and also a high self-discharge coefficient. Scott report that using an ionic conductive Li-Nafions binder and

Lithium-ion (Li-ion) – this type of battery is characterized by a Li-Nafions membrane improved battery's capacity with good rate
large power storage capacity with very good energy density/ capability and capacity retention [20]. It was shown that at a 50%
weight ratio. However, the limitations in the way of massive depth of discharge (DOD), LiCoO2/SrLi2Ti6O14 batteries have an
use of this type of battery are given by: high costs, a potential excellent specific charge power density of 3973 W kg  1 that can
for overheating and a limited life cycle. be attributed to the high diffusion capability of lithium and high

Lithium-ion Polymer – provides a greater life cycle than the electronic conductivity of the SrLi2Ti6O14 material [21]. Gummow
classical Li-ion batteries, but it presents a functional instability and He [22] present the recent developments in the study of
both in the case of an overload and in the case of battery Li2MnSiO4 as cathode material, due to its low cost, environmen-
discharges below a certain value. tally friendly and high theoretical capacity. Pei et al. [23] shown

Sodium Nickel Chloride (NaNiCl) – is also known as the “Zebra that even the zinc–air batteries can help to enhance energy
battery” and it uses a molten salt electrolyte with an operating efficiency, its practical specific energy is low, only about
temperature of 270–350 1C. It offers the advantage of having a 200 W h kg  1.
high stored energy density. The major disadvantages are Also, another factor is the lifetime of battery, which directly and
related to its operational safety and its storage for longer to a large extent influences the subsequent maintenance costs of
periods. purchasing an electric vehicle. Aging of lithium-ion cells, battery
charge/discharge mode, electrolyte system, thermal and energy
management system are inevitable phenomenon limiting the
The main characteristics of batteries currently developed and lifetime of battery [24]. Röder et al. [25] and Schmalstieg et al.
most used to equip electric vehicles are presented in Table 1 and [26] consider that undesirable side reactions during cycle or
Fig. 2. calendar aging affect directly the performance of all components
For applications that aim to power electric motors that equip of the lithium-ion cell. To improve the lifetime parameter,
electric vehicles, the batteries that offer the highest coefficient of researches done were focused on nanotechnology application in
stored energy density are preferred. The higher the value of this development of anode and cathode material [20,27–29]. This
coefficient, the higher the autonomy of the electric vehicle will be. opens an avenue of research into green chemistry and green
Thus, the need for further research to increase the energy density technologies for novel battery innovations.
of batteries that equip electric vehicles is of immediate impor-
tance, and also an important external factor in increasing the
penetration of the contemporary auto market by electric vehicles
[17–19]. 3. Life Cycle Assessment approaches on electric vehicles and
Currently researches on new materials for battery's cathode batteries
and anode are done to improve performances as capacity, cycle
stability, rate capability, conductivity and ion transport. Cheng and The present technologies used to build electric vehicles (and
also battery pack) are complex, taking into consideration the
Table 1 length and structure of production chain. The evaluation of
Technical characteristics of main battery types used for EVa. environmental impact due to relationship between inputs factors
Battery Specific Energy/ Power/ Self- Number of
(primary resources, energy, and materials) and output factors
technology energy Volume Weight discharge recharging (emissions, waste) can be done using Life Cycle Assessment
(type) (Wh/kg) coefficient coefficient coefficient cycles (LCA) approach (Fig. 3).
(Wh/L) (W/kg) (% per 24 h) LCA approach is essential for understanding the effects of
duration of a technology over another (or over external environ-
Pb-acid 40 70 180 1 500
Ni–Cd 60 100 150 5 1350 ment), to the entire life of product. But since the LCA analysis is
NiMH 70 250 1000 2 1350 based on the application of predefined scenarios there is an
Li-ion 125 270 1800 1 1000 element of uncertainty introduced in these typological studies.
Li-ion 200 300 3500 1 1000 Van der Bossche et al. highlight that the LCA of a product can
polymer
Na–NiCl 125 300 1500 0 1000
never be completely exhaustive and “as a consequence the analyst
has freedom to choose which degree of detail (…) to model to
a
Average values according to data from references [19,72–74]. assessed life cycle” [30].
 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012 1007

Fig. 3. LCA systemic structure for battery.

However, this tool provides the premises to avoid false conclu- vehicle product chain impacts and promoting clean electricity.
sions being a learning tool for strategic assessment of the technol- More comprehensive studies were done on comparative applica-
ogy, and having the possibility to identify the key improvement tion of LCA on electric, hybrid, gasoline and alternative fueled cars
areas [31]. [35,36]. The major conclusion was that for each type of vehicle the
A complete LCA involves four major steps (according to Inter- environmental impact along vehicle's lifetime depend by every
national Organization for Standardization – ISO), namely as phase of vehicle's production, in-service and end-of-life. The
follows: greenhouse effect of the hybrid and battery electric vehicles is
approx. 27% and 78% lower than for the gasoline vehicles.

Principles and Framework (ISO 14040). To optimize the selection process of EV's and PHEV's battery

Goal and Scope definition of investigation on a system or (taking into consideration the economical and environmental
product (ISO 14041). benefits), Shahi and Wang [37] used a simulation process based

Inventory analysis by collecting data and calculation, quantifi- on Pareto set points and PSAT™ algorithm. It was found that the
cation of inputs and outputs (ISO 14042). NiMH battery offer better fuel economy and Lithium-ion battery

Impact analysis of relevant (alleged) inputs and outputs flows yield the lowest operating costs and GHG emissions (compared to
improvement analysis by conclusions drawn from investiga- lead-acid batteries). Moreover, researchers studied the environ-
tion, and provide future direction related to performances of mental impact of NiMH and Lithium-Ion (LiMN2O4) cells in
product and/or system (ISO 14043). production and use, using also an LCA analysis [38]. The environ-
mental impact of the production and use of considered battery
The major limitation of LCA studies regarding the environ- cells was extended considering also the carbon dioxide, carbon
mental, economic and political sustainability of EV use are monoxide, sulfur dioxide and VOC emissions. The production and
imposed by the particularities of battery design and type, EV use use of the NiMH technology was found to have the highest
condition and type. environmental impact.
There are numerous LCA studies in battery technology for EV An important factor for a complete LCA is the recycling process.
reported in the literature. Peterson and Michalek investigated the The recycling process offer immediate benefits in terms of: less
net life cycle air emissions from Plug-in Hybrid Electric Vehicles energy use and reduce costs in producing components from
(PHEV) for different battery sizes and charging strategies for an recycled products, compared to new products manufactured from
average US driver [32]. The results show that emissions of CO2, SO2 raw materials, avoiding potential environmental hazards from
and NOx can be reduced with increasing battery size. The impact of disposal, imports and demand for scarce resources is reduced.
the electricity mix and use profiles for electric vehicles was also Currently, the recycling process is based on direct smelting
included in the study by Peterson and Michalek [32] which process of batteries. Valuable materials such cobalt, nickel, man-
concludes that EVs can be more sustainable from environmental ganese are recovered and sent to refining, and use for e.g. in the
perspective only if the technology follows requirements are full fit: manufacturing of stainless steel (from which the car body is
improvement of battery technology, environmentally balanced manufactured). Unfortunately, the lithium and rare earth elements
energy fashion and eco-driving use of vehicle [33]. go to the slag (as result of waste's thermal melting neutralization
Taking into consideration of present European electricity mix, process), which is used as aggregate in roadbeds and pavements.
Hawkins et al. showed that lifetimes of 150000 km for an EV, offer The recovering of rare earth elements from battery can be done by
the potential to decrease global warming potential (GWP) with different technologies (leaching process), but there is no existing
10% to 24% [34]. The potential to decrease further the GWP can be economic incentive for these processes. Still, there are discussions
obtain with a significant increase of EV lifetime, by reducing on this issue, highlighting the need of continuous and further
1008 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012

development of an efficient recycling process and an efficient intoxicating the environment [43] and its inherent living organ-
material re-use strategy. isms [44]. Lithium-ion batteries have also a relatively high carbon
Therefore further research is needed on the use of new (green) footprint (70 kg CO2/kW h) [45] and require considerable changes
materials, readily biodegradable and/or with high potential for in their technological development (including extraction from sea
recycling, for components of batteries used in electric vehicles. waters) [46] in order to satisfy the increasing energy requirements
It also important to mention that most of researches have been of the world [40]. Lithium-ion batteries are also becoming more
taking into consideration mainly the passenger car market, how- and more expensive as the lithium storage become more inacces-
ever future LCA analyses on the environmental impact of use sible and non-available [40]. This leads to the search for other
electric buses in urban transportation environment, are equally alternatives, which consider other metals such as magnesium [47]
critical as there is a potential that urban transportation can be an and aluminum [48]. However, the pivot of future battery technol-
extensive sector (and to part already is) for electric drive technol- ogies lies in the synthesis of red/ox systems with fully 1) recyclable
ogy. The particularities of batteries (weight, type, size, capacity, properties, 2) environmental and bio-friendly properties and 3)
specific energy, and cycle life) and exploitation conditions (traffic excellent electricity generation potentials. Such systems can only
congestion, driving attitude, passengers capacity, infrastructure rest in the combination of organic compounds at the anode
profile) are strong factors of influence for LCA approach of positions and natural electron-withdrawing compounds at the
environmental global impact. cathode positions, which create a reversible potential without the
loss of the reactivity of the underlying chemical reaction. Dis-
counting for lithium as the anode component where ever possible,
4. Green chemistry for novel battery technologies a look into the most actual organic compounds and their proper-
ties is derived, also including enzymatic systems, such as voltage-
Green chemistry and generation of green electricity represents gate potassium channels and proton channels, which make up the
an exciting avenue of portable energy as well as electric vehicle most exotic and high-potential bio-organic systems for the gen-
powering systems, which is independent from absence/presence eration of current.
of solar light or other renewable sources such as hydro-electric
power. In order to describe some innovations in the field of green
4.1. Organic compounds for novel battery technologies
chemistry, a brief introduction on the structure of a green portable
battery is elucidated.
Organic compounds have been tested both theoretically and
Any battery system relies on the magnitude of the reductive
experimentally as components in Lithium rechargeable batteries.
potentials of the inherent ionic compounds of the battery fluids.
The use of Lithium results as ubiquitous in the field of recharge-
For this reason, a series of challenges exist in replacing the current
able batteries, and the majority of the cathode compositions
and conventional methods, which are heavily focused on the use
encompass organic compounds in covalent crystals based on
of transition metals, with more environmental friendly systems.
carbonyl-containing and pyrene-containing groups, such as
Transition metals and metal compounds have a far higher reduc-
Li2C2O6 and pyrene-4,5,9,10-tetraone (Fig. 4) [49,50]. The former
tive potential than organic compounds (and atoms), and the main
has a theoretical gravimetric capacity Cth ¼ 589 mAh/g and the
element of organic compounds - carbon - offers a low potential in
latter of Cth ¼409 mAh/g. Although a high expected capacity
its ionic state, and readily forms covalent and inseparable bonds
results for these two types of organic cathode compounds, other
after oxidation leading to insoluble products from the electron
studies show that they quickly suffer for severe solubility in
transfer reactions. This makes carbon more suitable for biology
liquid organic electrolytes [51]. Solid silica nanoparticles have
than technology, and also Silicon, which is frequently used as a
been applied as substrates to reduce this problem with positive
replacement, offers too low red-ox potentials [39]. The develop-
results [52].
ment of green chemistry for novel battery technologies - to reduce
Another approach to reduce this problem has been through the
the environmental load from inconsistent recycling-procedures -
mitigation of the electrolyte via the accommodation of soluble
relies therefore on identifying novel organic systems that readily
quinonic cathode materials inside quasi-solid-state cells [53,54].
donate electrons and are not reduced to insoluble forms. In a
The solid state cells are assembled in a combined disk-format,
successful case of an organic compound applied in a battery, the
using the solid electrolyte as stacking layer, with a polyethylene
interchange of electrons proceeds from the oxidized and reduced
oxide film in between and the cathode paste in 5–7 mm in
states of the organic compound, generating the electric potential
diameter, all arranged on a carbon-current collector disk. The
(e  ) in the organic battery depending on the set of compounds. In
order to harvest this organic electric potential, a solvent phase
must be able to transfer electrons from the organic compounds,
across the conductive interconnection (wire) between the two
chambers that separate the organic compounds, and the excitation
potential for the organic pairs, must be so that one side of the
chambers has a generally higher total potential than the other
during its reduced state.
Identifying such compounds is at its infant stage, and several
biochemical and chemical factors, such as by-products, aggrega-
tion and cross-reactions inhibit a long-lasting bio-friendly battery
technology to emerge. The majority of emerging technologies of
more “green” properties depend therefore still on the use of
Lithium [40], which are ultimately not sustainable. Lithium-ion
batteries require the use of a transition metal, as mentioned above,
which is frequently Cobalt (alternatively Manganese or Nickel).
These metals are obtained from depleting natural resources and Fig. 4. Pyrene-4,5,9,10-tetraone structure. Four oxygen atoms generate an electron-
their cradle-to-grave cycle leads often to their release to the withdrawing effect on the planar aromatic moiety, which results in a quasi-polar
environment [41], affecting third-world countries [42] and property of the ketopyrene structure.
 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012 1009

entire stack is packed to form pellet-like ensembles, used in create a strong polarizing effect on these positively charge carbons
combination with the lithium component [53]. The organic com- (Fig. 6, blue spheres). This charge-transfer potential is known as
pound applied in this liquid quinonic cathode material was electronic coupling (Vcoup) or also as effective transfer integrals
tetracyanoquinodimethane (TCQDM – Fig. 5), and generated (Jeff) and is given by the form: Vcoup ¼(J-S(e1 þe2)/2)/(1  S2). Here
200 mA h/g capacity [53]. The electron transfer is facilitated by e1 is the energy of the highest occupying electrons of one TCQDM
the electron-rich nitrogen groups in TCQDM, assisted by the π–π molecule and e2 is the energy of the highest occupying electrons of
electron stacking effects between quinone rings, which contribute the second TCQDM molecule (Figs. 5 and 6). S is the overlap
to the generation of an electrostatic tension in the liquid organic integral, while J is charge-transfer integral. The calculations are
material. This effect is clearly seen in Fig. 6, a density functional performed with the Amsterdam Density Functional package [55]
analysis of the properties of TCQDM and its charge transfer and show that the TCQDM molecules are better carriers of electric
potentials. This analysis displays the charge-transfer potential of current via n-type operational mode (transfer through electron-
two adjacent TCQDM molecules, which transfer the charge from dense sites), with a charge-transfer potential (V) of  0.00886eV.
their aromatic rings, to the positively charged carbon atoms bound TCQDM is less efficient for p-type operational mode (transfer
directly to the nitrogen atoms (Fig. 6). The role of the nitrogen is to through Fermi-holes), as its equivalent charge-transfer
(V) potential is 0.01549 eV, about 57% lower in efficiency. This
pattern of charge transfer is shown very nicely using a Bader
analysis [56] which displays a pattern of the charge transfer
between two TCQDM molecules (Fig. 6), and can be readily applied
to other systems before synthesis and testing.
Organic cathode compounds are as mentioned shown to suffer
for severe solubility in liquid organic electrolytes [51], however for
other organic materials, such as for polymeric organic cathodes
[57] the opposite can occur, where the polymeric organic sub-
stances tend to aggregate and inhibit the electron flow in the Li þ
conduction path [58] and rather reduce capacity of the battery
system. 2,5-dihydroxy benzoquinone (Fig. 7) is an additional
quinone compound which has been used with silica room-
temperature ionic liquid as electrolyte, and generated a battery
capacity of 300 mA h/g, with a power density of 540 Whk/g,
adapted also to solid-state cells [53]. Additionally a novel devel-
opment of particular interest, lies in the organic compound-based
Li-batteries with organic pillar [5]quinone (Fig. 8) cathode and
composite polymer electrolyte (CPE) [59] which render an initial
capacity of 418 mA h/g, at an operation voltage of 2.6 V. The use of
(PMA)/poly(ethylene glycol) (PEG)-based gel polymer electrolyte,
Fig. 5. Tetracyanoquinodimethane (TCQDM) structure. The four polarizing cyano-
which is fundamental for the CPE for quasi-solid lithium batt-
nitrogens represent an electron-rich group which readily facilitates polarization eries, facilitates the operational capacity of the battery with a
effects on the molecules as a whole. calix[n]quinone material at the cathode delivering capacities to
379 mA h/g after 100 cycles. Usage of calyx-like mega-organic
compounds (Fig. 8) invoke the potential of assembling nanosized
compounds in dimensions comparable to fullerenes and small
nanomaterials [60,61], which selectively donate several electron-
pairs via the oxygens on the inherent quinone groups. This
rationale applies the advantage of durable and stable nanostruc-
tured materials, with atomic and electronic electrolytic properties
on designated electrophilic atoms of groups with lithium-trapping
properties. Other novel forms of multi-quinone systems are
organic ensembles for organic-compound-based batteries which
can be inspired by symmetries and dimensions of large polycyclic
aromatic hydrocarbons, such as the asphaltenes and the large
coronenes as the hexa-peri-hexabenzo(bc,ef,hi,kl,no,qr)coronene
[62]. This relationship between exploiting large π-systems and
planarity can be an effective path of developing greener solutions
for novel battery technologies based on carbon-systems.

Fig. 6. The charge transfer patterns for two TCQDM molecules. The blue atoms
designate the positively charged carbon atoms, bound to the nitrogen groups. The
red lines with red dots show direct interactions between these positively charged
carbons and the aromatic rings, with gain a weak negative charge, due to the
conjugated pi-electrons. The nitrogen atoms are neutral and shown as white
spheres at the absolute extremities. Green dots depict atom-group interactions,
which are frequently found at centers of aromatic rings or between three or several Fig. 7. 2,5-dihydroxy benzoquinone structure. The structure depicts a third
non-bonded atoms. (For interpretation of the references to color in this figure combination of polar electron-withdrawing atoms (O) in combination with planar
legend, the reader is referred to the web version of this article). pi-electron rich rings.
1010 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012

Fig. 8. The organic pillar for lithium ion accommodation (C35H20O10). This organic mega-structure applies the combination of multiple quinone rings combined with oxygen
atoms with lone electrons, which readily form covalent bonds with Li atoms.

Fig. 9. The voltage-gated potassium channel protein [71]. Only one domain is shown for simplicity. The red regions show the voltage-sensors on the protein, which act on
the inside and outside of the membrane to trigger activation during a fluctuation in overall charge-potential. The sensor is composed of positively charged residues, which
trigger rearrangements of non-covalent bonds within the framework of the proteins interactions. (For interpretation of the references to color in this figure legend, the
reader is referred to the web version of this article).

4.2. Enzyme systems leak channels (sodium leak channels [69]). One of these enzyme
systems is illustrated in Fig. 9. The enzymes were calculated to
Enzymes and proteins represent a poorly area in the field of generate respectively a channel conductance of 1.57  103 S/m²,
nano-energetics and as bio-energy sources assembled for battery- 3.20  103 S/m², 5.91  102 S/m² and 3.43  101 S/m² when present
structures. The rationale of using enzymes to produce electricity in the biological environment. A combination of voltage-gated
through generation of gradients of proton or ion concentrations potassium channels has also been proposed in a similar scenario of
has been briefly discussed [40] and proposed theoretically [63], synthetic membranes theoretically [63]. Here, the rationale
however its realization lies in the development of bionanotech- exploits the imbalance formed between inward oriented channel
nology applications that merge proteins and nanomaterials for proteins (pumping ions inward) and outward oriented channels,
nano- and micro-electronic devices and structures, which can at a which expectedly form a competition against Le Chateliers’ prin-
more developed stage be assembled into larger structures, based ciple of spontaneous ion migration, as these proteins are triggered
on biological and biodegradable components. A series of proteins by molecular voltage sensor domains (Fig. 9) [63]. Indeed, if
can be used for such approaches, and advances in nanotechnology assimilable in a future engineering of nanomaterials, osmotic
have already merged the ATPase proton pump in experimental membranes and enzymes, as one of the many avenues of incor-
nano-circuits [64]. In parallel with these developments, a study porating enzymes as energy-production units, can be feasible.
from 2007 proposed a theoretical model for designing artificial These types of bio-battery structures have the potential of gen-
cells to harness ion concentration gradient to generate electric erating milli-watt levels during single-pulse energy output, for one
current [65]. The study proposed a system where the ion concen- nanocell and an equivalent effect of 0.542 W/m² in a maximum
tration gradient is produced in an artificial cell composed of power output signal [65]. The modeling by Xu and Lavan [65]
membranes with incorporation of four main channel-type shows also that the maximum energy conversion efficiency with
enzymes: the sodium/potassium ATPase pumps [66], Voltage- the modeled system in an artificial device is expected to be higher
gated Naþ channels [67], inward rectifier Kþ channels [68] and than the native biological cells (axons) compared (from the
 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012 1011

organism electric eel), as these are subjected to physiological 3) a stable and non-solvated core, which forms the stability of the
parameters, such as limitations in substrate availability and auto- biosystem and gives it a fixed amount of degrees of freedom
regulative responses from the genome. The crucial differences within its form and shape (Fig. 10). This subdivision of chemistry-
between bio-batteries and native organic systems with potential types (hydrophilic, amphiphilic, and hydrophobic) is nearly pre-
of forming gradient, lies in the simplicity of the cell. Any cell of sent in all biosystems, in order to provide them the ability to
organic origin represents a complexity based on the role of DNA, conform with the environment without loosing structure and
RNA and nucleus in driving the cell activity. However, in a function. This topology is native for all systems, including
biobattery, the envisioned structures are strongly simplified, to voltage-gated channels or lipo-proteins and proves central for
use one or several biomolecular systems that are 1) stable in the future battery systems.
desired solution for electric current generation, 2) are stable
against microbial degradation and 3) are not aggregating or
collapsing at the active sites or at the domain hinges which 5. Conclusions
propagates the electric generation function. These terms are best
ascertained using nanomaterials and coatings outside the biologi- Electric vehicle batteries rely to date in their majority on metal-
cal components, as a stable insulating material. The combination systems, as most metal system provide the most optimal red/ox
of green-chemistry components, such as TCQDM (Fig. 6) or other potentials and often give electrochemical simple environments to
similar carbon-based systems can be combined in a separate generate electric current. However, their life cycle and analysis of
chamber or system, without direct contact to the biocomponent their use shows that batteries are frequently associated with
of the battery, as the reactivity between amino acids and extra- pollution and environmental burdens, and the need to innovate
neous chemistries will by necessity result in undesired chemical biologically degradable and bio-dependent systems for battery
reactions. As an important factor for biosystems, a series of cellular structures is eminent, if the sector of consumer electronics and
components which can be candidates of interacting with nano- electric transport is to be subjected to a sustainable development.
components have recently been published [70]. The various The technologies within green chemistry solutions show several
parameters associated with these cell components as well as their systems which rely on aromatic rings, which quickly provide good
compatibility with nanocomponents is defined within the various charge-transfer properties, and use carbon, nitrogen and oxygen as
classes of chemical properties, such as hydrophobicity and hydro- main compounds. However, only a few of carbon-based technol-
philicity, porosity and crystallinity [70]. The crucial properties of ogies are developed to testable battery systems, and more are
any biosystem for implementation as a battery system lies in its required to be developed in order to make the field of portable
dynamic interchange with a solvent phase: any protein or bio- electricity and electric vehicle powering sustainable. The use of
component (including membranes) have three main sections: 1) a enzymes and biological systems to generate portable electricity
water-solvated surface which traps and interacts with water finds relevance in several theoretical however few empirical
through hydrogen-bonds and dielectric exchange, 2) a intermedi- achievements. Their structures rely on the generation of electric
ate section which forms the shape of the biosystem, through current from formation of gradients across membranes, and can
intermolecular non-covalent bonds which give it flexibility and therefore provide portable electricity up to milliwatt levels. Except
for the inclusion of solar-cell technologies, biobatteries can be a
promising avenue of green battery technologies for the future and
can reduce the environmental burden compared to present day
metal-lithium batteries, both for portable systems as well as the
automotive industry.

References

[1] Romm J. The car and fuel of the future. Energy Policy 2006;34:2609–14.
[2] Notter DA, Gauch M, Widmer R, Wager P, Stamp A, Zah R, et al. Contribution
of Li-ion batteries to the environmental impact of electric vehicles. Environ Sci
Technol 2010;44:6550–6.
[3] San Román TG, Momber I, Abbad MR, Sánchez Miralles Á. Regulatory frame-
work and business models for charging plug-in electric vehicles: Infrastruc-
ture, agents, and commercial relationships. Energy Policy 2011;39:6360–75.
[4] Pelejero C, Calvo E, McCulloch MT, Marshall JF, Gagan MK, Lough JM, et al.
Preindustrial to modern interdecadal variability in coral reef pH. Science
2005;309:2204–7.
[5] Wood HL, Spicer JI, Widdicombe S. Ocean acidification may increase calcifica-
tion rates, but at a cost. Proc R Soc Lond B Biol 2008;275:1767–73.
[6] Hoegh-Guldberg O, Mumby P, Hooten A, Steneck R, Greenfield P, Gomez E,
et al. Coral reefs under rapid climate change and ocean acidification. Science
2007;318:1737–42.
[7] Barnett TP, Adam JC, Lettenmaier DP. Potential impacts of a warming climate
on water availability in snow-dominated regions. Nature 2005;438:303–9.
[8] Hansen J, Nazarenko L. Soot climate forcing via snow and ice albedos. Proc Natl
Acad Sci USA 2004;101:423–8.
Fig. 10. The roles and arrangement of biosystems. Light-blue sphere: the water- [9] Wirasingha SG, Schofield N, Emadi A. Plug-in hybrid electric vehicle develop-
soluble interface of the biomolecular system with its role in interacting with the ments in the US: trends, barriers, and economic feasibility. In: Proceedings of
IEEE vehicle power and propulsion conference 2008, VPPC'08; 2008. p. 1–8.
water-phase (molecules around); the blue sphere: the intermediate moiety of any
[10] Sadek N. Urban electric vehicles: a contemporary business case. Eur Transp
biosystem with a flexible non-covalent network to allow dynamical properties of
Res Rev 2012;4:27–37.
the system to exert its function and interact with its surroundings; the red core: the [11] Mariasiu F. Energy Sources Management and Future Automotive Technologies:
compact and structure-stabilizing non-soluble moiety which provides shape Environmental Impact. Int J Energy Econ Policy 2012;2:342–7.
stability and a limitation of degrees of conformational freedom for the system in [12] Delucchi M, Yang C, Burke A, Ogden J, Kurani K, Kessler J, et al. An assessment
order to prevent for collapse or dissolution with its surroundinngs. (For interpreta- of electric vehicles: technology, infrastructure requirements, greenhouse-gas
tion of the references to color in this figure legend, the reader is referred to the web emissions, petroleum use, material use, lifetime cost, consumer acceptance
version of this article). and policy initiatives. Philos Trans R Soc A 2014;372:203–25.
1012 S. Manzetti, F. Mariasiu / Renewable and Sustainable Energy Reviews 51 (2015) 1004–1012

[13] Varga BO. Energy management of electric and hybrid vehicles dependent on [42] Nnorom I, Osibanjo O. Overview of electronic waste (e-waste) management
powertrain configuration. Cent Eur J Eng 2012;2:253–63. practices and legislations, and their poor applications in the developing
[14] Damiani L, Repetto M, Prato AP. Improvement of powertrain efficiency countries. Resour Conserv Recycl 2008;52:843–58.
through energy breakdown analysis. Appl Energy 2014;121:252–63. [43] Pan K, Wang W-X. Trace metal contamination in estuarine and coastal
[15] Sutikno T, Idris NRN, Jidin A. A review of direct torque control of induction environments in China. Sci Total Environ 2012;421:3–16.
motors for sustainable reliability and energy efficient drives. Renew Sustain [44] Underwood E. Trace elements in human and animal nutrition. 4th ed..
Energy Rev 2014;32:548–58. Burlington: Elsevier Science; 2012.
[16] Matheys J, Van Mierlo J, Timmermans J-M, Van den Bossche P. Life-cycle [45] Soeno Y, Ino H, Shiratori K, Nakajima K, Halada K. Exergy analysis to integrate
assessment of batteries in the context of the EU directive on end-of-life environmental impacts. In: Proceedings of the fifth international conference
vehicles. Int J Veh Des 2008;46:189–203. on ecobalance, Nov. 6-8, Tsukuba, Japan; 2002. p. 841–4.
[17] Mortazavi M, Wang C, Deng J, Shenoy VB, Medhekar NV. Ab initio character- [46] Hoshino T. Lithium resources recovery from seawater by electrodialysis using
ization of layered MoS2 as anode for sodium-ion batteries. J Power Sources novel ion exchange membrane. Electrochem Soc Trans 2014;58(48):173–7.
2014;268:279–86. [47] Qingsong Z, Yanna N, Yongsheng G, Jun Y, Jiulin W. Electrolytes for recharge-
[18] Cao W, Li Y, Fitch B, Shih J, Doung T, Zheng J. Strategies to optimize lithium-ion able magnesium batteries. Prog Chem 2011;23:1598–610.
supercapacitors achieving high-performance: Cathode configurations, lithium [48] Egan D, Ponce de León C, Wood R, Jones R, Stokes K, Walsh F. Developments in
loadings on anode, and types of separator. J Power Sources 2014;268:841–7. electrode materials and electrolytes for aluminium–air batteries. J Power
[19] Suberu MY, Mustafa MW, Bashir N. Energy storage systems for renewable Sources 2013;236:293–310.
[49] Armand M, Grugeon S, Vezin H, Laruelle S, Ribière P, Poizot P, et al.
energy power sector integration and mitigation of intermittency. Renew
Conjugated dicarboxylate anodes for Li-ion batteries. Nat Mater
Sustain Energy Rev 2014;35:499–514.
2009;8:120–5.
[20] Cheng H, Scott K. Improving performance of rechargeable Li-air batteries from
[50] Chen H, Armand M, Demailly G, Dolhem F, Poizot P, Tarascon JM. From
using Li-Nafions binder. Electrochim Acta 2014;116:51–8.
biomass to a renewable LiXC6O6 organic electrode for sustainable Li-ion
[21] Liu J, Sun X, Li Y, Wang X, Gao Y, Wu K, et al. Electrochemical performance of
batteries. ChemSusChem 2008;1:348–55.
LiCoO2/SrLi2Ti6O14 batteries for high-power applications. J Power Sources
[51] Huang W, Zhu Z, Wang L, Wang S, Li H, Tao Z, et al. Quasi-solid-state
2014;245:371–6.
rechargeable lithium-ion batteries with a Calix [4] quinone cathode and gel
[22] Gummow RJ, He Y. Recent progress in the development of Li2MnSiO4 cathode
polymer electrolyte. Angew Chem 2013;125:9332–6.
materials. J Power Sources 2014;253:315–33.
[52] Genorio B, Pirnat K, Cerc-Korosec R, Dominko R, Gaberscek M. Electroactive
[23] Pei P, Wang K, Ma Z. Technologies for extending zinc–air battery's cycle life: a
organic molecules immobilized onto solid nanoparticles as a cathode material
review. Appl Energy 2014;128:315–24. for lithium-ion batteries. Angew Chem Int Ed 2010;49:7222–4.
[24] Sahapatsombut U, Cheng H, Scott K. Modelling of electrolyte degradation and [53] Hanyu Y, Ganbe Y, Honma I. Application of quinonic cathode compounds for
cycling behaviour in a lithium–air battery. J Power Sources 2013;243:409–18. quasi-solid lithium batteries. J Power Sources 2013;221:186–90.
[25] Röder P, Stiaszny B, Ziegler JC, Baba N, Lagaly P, Wiemhöfer HD. The impact of [54] Hanyu Y, Honma I. Rechargeable quasi-solid state lithium battery with organic
calendar aging on the thermal stability of a LiMn2O4–Li(Ni1/3Mn1/3Co1/3)O2/ crystalline cathode. Sci Rep 2012;2:453–9.
graphite lithium-ion cell. J Power Sources 2014;268:315–25. [55] Bérces AB, Boerrigter PM, Cavallo L, Chong DP, Deng L, Dickson RM, et al.
[26] Schmalstieg J, Käbitz S, Ecker M, Sauer DU. A holistic aging model for Li ADF2004.01. SCM, theoretical chemistry. Amsterdam, The Netherlands: Vrije
(NiMnCo)O2 based 18650 lithium-ion batteries. J Power Sources Universitiet; 2004. 〈http://www.scm.com〉.
2014;257:325–34. [56] Bader FW. Atoms in molecules: a quantum theory. New York: Oxford
[27] Cheng H, Scott K. Nano-structured gas diffusion electrode – a high power and University Press; 1994.
stable cathode material for rechargeable Li-air batteries. J Power Sources [57] Zhan L, Song Z, Zhang J, Tang J, Zhan H, Zhou Y, et al. PEDOT: cathode active
2013;235:226–33. material with high specific capacity in novel electrolyte system. Electrochim
[28] Jiang Y, Zhang D, Li Y, Yuan T, Bahlawane N, Liang C, et al. Amorphous Fe2O3 Acta 2008;53:8319–23.
as a high-capacity, high-rate and long-life anode material for lithium ion [58] Le Gall T, Reiman KH, Grossel MC, Owen JR. Poly (2, 5-dihydroxy-1, 4-benzo-
batteries. Nano Energy 2014;4:23–30. quinone-3, 6-methylene): a new organic polymer as positive electrode
[29] Zhou G, Pei S, Li L, Wang DW, Wang S, Huang K, et al. A graphene–pure-sulfur material for rechargeable lithium batteries. J Power Sources 2003;119:316–20.
sandwich structure for ultrafast, long-life lithium–sulfur batteries. Adv Mater. [59] Zhu Z, Hong M, Guo D-S, Shi J, Tao Z, Chen J. All-solid-state lithium organic
2014;26:625–31. battery with composite polymer electrolyte and Pillar[5]quinone cathode. J
[30] Van den Bossche P, Matheys J, Van Mierlo J. Battery environmental analysis. Am Chem Soc 2014;136(47):16461–4.
In: Pistoia G, editor. Electric and hybrid vehicles: amsterdam. Elsevier; 2010. [60] Chamberlain TW, Gimenez-Lopez MdC, Khlobystov AN. Carbon nanotubes as
p. 347–74. containers. In: Guldi DM, Nazario M, editors. Carbon nanotubes and related
[31] Nordelöf A, Messagie M, Tillman A-M, Söderman ML, Van Mierlo J. Environ- structures. Weinheim: Wiley-VCH; 2010. p. 349–84.
mental impacts of hybrid, plug-in hybrid, and battery electric vehicles – what [61] Warner JH, Watt AA, Ge L, Porfyrakis K, Akachi T, Okimoto H, et al. Dynamics
can we learn from life cycle assessment? Int J Life Cycle Assess of paramagnetic metallofullerenes in carbon nanotube peapods. Nano Lett
2014;19:1866–90. 2008;8:1005–10.
[32] Peterson SB, Michalek JJ. Cost-effectiveness of plug-in hybrid electric vehicle [62] Herwig PT, Enkelmann V, Schmelz O, Müllen K. Synthesis and structural
battery capacity and charging infrastructure investment for reducing US characterization of hexa-tert-butyl-hexa-peri-hexabenzocoronene. its radical
gasoline consumption. Energy Policy 2013;52:429–38. cation salt and its tricarbonylchromium complex. Chem - Eur J
[33] Faria R, Marques P, Moura P, Freire F, Delgado J, de Almeida AT. Impact of the 2000;6:1834–9.
electricity mix and use profile in the life-cycle assessment of electric vehicles. [63] Manzetti S. Renewable energy driven by Le Chatelier's principle, enzyme
Renew Sustain Energy Rev 2013;24:271–87. function, and non-additive contributions to ion fluctuations: a hypothesis in
[34] Hawkins TR, Singh B, Majeau-Bettez G, Strømman AH. Comparative environ- biomechanical and nanotechnology energy theory. J Nanotechnol
mental life cycle assessment of conventional and electric vehicles. J Ind Ecol 2011;2011:1–8.
[64] Huang S-CJ, Artyukhin AB, Misra N, Martinez JA, Stroeve PA, Grigoropoulos CP,
2013;17:53–64.
et al. Carbon nanotube transistor controlled by a biological ion pump gate.
[35] Boureima F-S, Messagie M, Matheys J, Wynen V, Sergeant N, Van Mierlo J, et al.
Nano Lett 2010;10:1812–6.
Comparative LCA of electric, hybrid, LPG and gasoline cars in Belgian context.
[65] Xu J, Lavan DA. Designing artificial cells to harness the biological ion
World Electr Veh J 2009;3:1–8.
concentration gradient. Nature Nanotechnol 2008;3:666–70.
[36] Sergeant N. An LCA tool for conventional and alternative vehicles. Association
[66] Ogawa H, Shinoda T, Cornelius F, Toyoshima C. Crystal structure of the
EDT editor. In: Proceedings of the 23rd international electric vehicle sympo-
sodium-potassium pump (Na þ , K þ -ATPase) with bound potassium and
sium and exposition 2007, EVS 2007 (Battery, Hybrid, Fuel Cell) – sustain-
ouabain. Proc Natl Acad Sci 2009;106:13742–7.
ability: the future of transportation; 2007. p. 466–74. [67] Armstrong CM. Voltage-gated K channels. Sci Signal 2003;188:10–24.
[37] Shahi S.K., Wang G.G. Plug-in hybrid electric vehicle battery selection for [68] Lu Z, MacKinnon R. Electrostatic tuning of Mg2 þ affinity in an inward-rectifier
optimum economic and environmental benefits using pareto set points and K þ channel. Nature 1994;371(6494):243–6.
PSAT™. In: Proceedings of the 2010 ASME design engineering technical [69] Ren D. Sodium leak channels in neuronal excitability and rhythmic behaviors.
conferences and computers in engineering conference. Montreal, Canada; Neuron 2011;72:899–911.
2010. p. 701–13. [70] Nel AE, Mädler L, Velegol D, Xia T, Hoek EM, Somasundaran P, et al.
[38] Gediga J. Comparison of two different types of battery cells for cars – Understanding biophysicochemical interactions at the nano–bio interface.
Environmental impact of NiMH and LiMn2O4 cells – in production and use. Nat Mater 2009;8:543–57.
In: Proceedings of the 22nd International battery, hybrid and fuel cell electric [71] Tao X, Lee A, Limapichat W, Dougherty DA, MacKinnon R. A gating charge
vehicle symposium & exposition (EVS-22), Yokohama, Japan, Oct. 23–28; transfer center in voltage sensors. Science 2010;328:67–73.
2006. p. 1124–30. [72] Kloess M. The role of plug-in-hybrids as bridging technology towards pure
[39] Bard AJ, Parsons R, Jordan J. Standard potentials in aqueous solution. New electric cars: an economic assessment. 〈http://publik.tuwien.ac.at/files/Pub
York: Marcel Dekker; 1985. Dat_191393pdf〉, 2009, (accessed May 2014).
[40] Armand M, Tarascon J-M. Building better batteries. Nature 2008;451:652–7. [73] Husain I. Electric and hybrid vehicles: design fundamentals. 2nd ed.. Boca
[41] Wong CS, Wu S, Duzgoren-Aydin NS, Aydin A, Wong MH. Trace metal Raton FL: CRC press; 2010.
contamination of sediments in an e-waste processing village in China. Environ [74] Helmers E, Marx P. Electric cars: technical characteristics and environmental
Pollut 2007;145:434–42. impact. Environ Sci Eur 2012;24:14–29.