AIP Conference Proceedings 1597 , 204 (2014) https:doi.org10.10631.4878489 1597 , 204 [631860]

AIP Conference Proceedings 1597 , 204 (2014); https://doi.org/10.1063/1.4878489 1597 , 204
© 2014 AIP Publishing LLC.Battery packaging – Technology review
Cite as: AIP Conference Proceedings 1597 , 204 (2014); https://doi.org/10.1063/1.4878489
Published Online: 17 February 2015
Eric Maiser
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Battery Packaging – Technology Review
Eric Maiser
The German Engineering Federation (VDMA), Ba ttery Production In dustry Group, Lyoner Str. 18,
60528 Frankfurt am Main, Germany

Abstract. This paper gives a brief overview of battery packaging concept s, their specific
advantages and drawbacks, as well as the importance of packagin g for performance and cost.
Production processes, scaling and automation are discussed in d etail to reveal opportunities for
cost reduction. Module standardization as an additional path to drive down cost is introduced. A
comparison to electronics and ph otovoltaics production shows “lessons learned” in those related
industries and how they can accelerate learning curves in batte ry production.
Keywords: Battery Packaging, Production, Pro cesses, Process Equipment, En gineering,
Backend Design, Standardization, Lithium Ion.
PACS: 82.47.Aa; 82.47.Cb; 81.20.Wk; 88.85.Hj; 88.85.J

INTRODUCTION

Although worldwide battery demand today is mostly driven by aut omotive starter
batteries, portable computers a nd cell phones, high-power appli cations like electric
vehicles (EV) or storage for renewable energy set the scene for the latest interest in
rechargeable battery technology. Reliability and cost are drive rs for success. Besides
innovations in cell chemistries and package design the alterati on from low volume
manufacture to mass production is one of the grand challenges i n bringing high-power
batteries into viable markets. De sign for manufacturability, pr oduction processes and
equipment as well as factory automation play a vital role in ac hieving this goal.
Different cell chemistries basically define the essence of a ba ttery and lay the
foundations for its suitability for a specific application – from consumer to industrial,
from stationary to mobile, optimized for high power or high ene rgy. Despite this
important electrochemical background, however, it is the packag ing that greatly
influences important performance parameters like lifetime, cycl ability, ruggedness,
safety and – most of all – cost. Overall, packaging adapts the battery to the specific
needs of an application: sealing, form factor, temperature and charge monitoring as
well as overall management are determined by the design and mak e of cells, modules
and packs. Especially for lithium ion chemistries a battery man agement system is
essential to create a reliable, lasting and safe battery – it is thus an important part of
the package.
Review on Electrochemical Storage Materials and Technology
AIP Conf. Proc. 1597, 204-218 (2014); doi: 10.1063/1.4878489
© 2014 AIP Publishing LLC 978-0-7354-1231-6/$30.00
204

Packaging technology involves several levels: The smallest unit of a battery is the
electrochemical cell, consisting of a cathode and an anode embe dded in an electrolyte
for ion migration. An insulating separator between cathode and anode prevents short
circuits. Small batteries, e.g. for consumer applications like flashlights, remote
controls, etc., just consist of one electrochemical cell – therefore the packaging on cell
level already defines the outward appearance. For higher voltag es or higher capacities
several electrochemical cell units are connected in parallel or in series, or both.
Lithium ion cathode-separator- anode stacks or jelly rolls are still called “ cells”.
Several of these cells are connected to modules , which contain individual cell
monitoring and temperature control. The assembly of modules for m a battery pack
(Fig. 1).

FIGURE 1. Example for packaging of a high-power automotive traction batt ery: (1) shows a prismatic
lithium-ion cell package. Several of these cells are put togeth er to form modules (2). They are
assembled with a battery management system (BMS), thermal manag ement, and electronic components
to form a battery pack (3). The battery management system monit ors the cells and the battery,
continuously controlling current and voltage, as well as temper ature and charge status. Reprinted with
permission of Robert Bosch GmbH.

PACKAGING TECHNOLOGY

Cell packaging designs and their combinations in modules and ba ttery packs are
offered in a huge variety, for primary and secondary batteries, and for different
applications. The aim of this paper is not to give a comprehens ive overview, since this
is already done elsewhere, e.g. [1,2,3] and references therein. We focus on the most
common examples for packaging technology, processing and manufa cturing issues
with special emphasis on high power / high energy secondary bat teries, especially with
lithium ion (Li-ion) chemistries.

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Cell Packaging Concepts

All basic concepts of cell packaging are given in [1]. A good o verview of historical
cell packaging concepts and the year of their introduction is g iven in [2]. A
comprehensive insight into standardisation of cell packages use d in common primary
and secondary battery types for c onsumer and light industrial u se is given in [3].

Cylindrical Cell

The cylindrical packaging design was an early form of mass-produced batteries a nd
is still very popular today. The biggest advantage is the mecha nical stability of the
cylinder, which naturally withstands internal pressures without deformation. A first
standard introduced already in 1896 was the big F-cell original ly used for lanterns. As
form factors became smaller, new standards were created with le tters counting
upwards: D, C, AA, and AAA are still very common today for all kinds of consumer-
type applications (Fig. 2). Secondary batteries of those packag ing types use mostly
Nickel-Cadmium (NiCd) and Nickel -Metal-Hydride (NiMH) chemistri es. They
contain one electrochemical cell.

FIGURE 2. Common consumer type battery packages, from left to right: a l arge 4.5 Volt battery, a
D-cell, a C-cell, an AA-cell, an AAA-cell, an AAAA-cell, an A23 battery, a 9 Volt (PP3) battery, and a
pair of button cells (CR2032 and LR44). Picture and caption rep rinted from [3].

Although not widely used today, some manufacturers chose cylind rical packages
even for lead-acid batteries (Fig. 3). A package with small, cy lindrical lead-acid cells
containing spirally-wound electrodes equivalent in size to the conventional D-cell
resulted from research started in 1967. These cells were the fi rst to use a separator
material consisting of microfiber glass paper, now generally referred to as “absorbent
glass mat” (AGM). The first commercially availab le AGM cell on the market was th e
Cyclon, patented by Gates Rubber Corporation in 1972 and now pr oduced by Enersys
[4]. The electrolyte is held in the glass mats, as opposed to f reely flooding the plates.
This configuration significantly increases packaging density in the cell, especially with
spiral winding of the cells [5]. This way, breaking of the plat es does not occur so
easily compared to the flooded type, which makes AGM lead-acid batteries very
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attractive for rugged environments where vibrations or high acc elerations occur, e.g.
in industrial robots, military, construction machines, motorspo rts, etc.

FIGURE 3. Cylindrical lead-acid batteries. Left: Cyclon was the first co mmercially available AGM
lead-acid battery. Picture: Enersy s. Right: Spiral-cell lead-ac id with different terminal configuration
built in a rectangular case to Battery Council International (B CI) specifications. Reprinted with
permission of Johnson Controls Autobatterie GmbH & Co. KGaA.

As a result of higher packaging density, AGM lead-acid batterie s have a low
internal resistance, can deliver high currents and promise a re latively long service life,
as well as deep-cycle stability. With the electrolyte soaked in the glass mats, they also
withstand low temperatures more easily [6]. With start-stop fea tures and higher energy
requirements in modern cars, AGM will probably become more popu lar in the future.
All the positive effects, however, come at a higher manufacturi ng cost.
On the Li-ion side a standard differing from the above mentione d consumer-type
cell sizes (F to AAAA) for cylindical packaging was established in the mid 1990s: the
18650 cell, 18 denoting the diameter, 65 denoting the length im millimeters. It has a
total mass of about 45 grams, including inactive material and p ackaging [7] and a
capacity ranging from 1.2 to 3 Ah, depending on cell chemistry [2]. It contains one
electrochemical cell, with cathode, anode and separator cut in stripes and rolled into a
metal can. The 18650 and the larger formats derived from it are very common in
battery packs for laptop PCs, electric bicycles and power tools . The packaging density
when grouping cylindrical cells is low due to their round shape , and the cell case is
comparatively heavy. However, air can easily circulate through a module or battery
pack with cylindrical cells, which eases cooling.

Prismatic Cell

Whereas the packaging of, e.g., consumer and starter batteries have been widely
standardized, manufacturers of Li-ion batteries introduced new formats when
requirements arising from product designs changed. This becomes obvious e.g. for
mobile phones, digital still cameras, video cameras, or tablet computers. Batteries for
those applications mostly have a box-like appearance called prismatic . There is no
standard with respect to aspect ratio or size. Prismatic cells have also been chosen for
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high power applications like traction batteries for cars (Fig. 1). Older types of
prismatic batteries also exist for above mentioned consumer bat teries (4.5 V and 9 V
examples in Fig. 2). Prismatic ce lls can contain one or more el ectrochemical cell units.

FIGURE 4. Three different sizes for Li-ion batteries (left to right): po uch cell, cylindrical cell, and
prismatic cell, respectively. Reprinted with permission of Jeff rey Sauger, General Motors Corp.

For Li-ion prismatic cells, cathodes, anodes and separators are also manufacured in
long stripes, wound up and then pressed to fit into the prismat ic container. Compared
to cylindrical cells, more stress is induced on the bent parts of the jelly roll in the
corners, which can be a problem for the electrode coating or el ectrolyte distribution.
The prismatic cell allows flexible design and improves packagin g density in a module
or pack. However, mechanical stress on the container is higher and thermal
management becomes more comple x than in a pack of cylindrical c ells.

Pouch Cell

Pouch cells are a somewhat minimalistic approach to packaging, becaus e they do
not have a rigid container any more. In fact, they are only sea led by flexible foil, that
is why they are also called “coffee bag cells”. Furthermore, cathodes, separators and
anodes are stacked instead of wound. This approach increases pa ckaging density to the
maximum and saves weight, thus increasing energy density of the cell. This type of
packaging is used only for Li-ion chemistries. Instead of a liq uid electrolyte, a
polymer electrolyte also acting as separator is sometimes used in this configuration.
Pouch cells usually have more than one electrochemical cell ins ide.
These very flat cells perfectly fit e.g. into tablet computers (capacities around
4 Ah). They are also employed for high-power and for high-energ y (EV) applications
(capacity example: 20 Ah A5-size with 20 cathode, 20 anode and 40 separator sheets,
respectively [8]). High currents either in charging or discharg ing mode result in
internal pressure. Serious swellin g of the package occurs when the cell is overheated
or shortened. Swelling occurs as a normal process during the in itial charging step
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(formation), though. To cope with that, manufacturers usually o versize the package,
resulting in a separate “bag” to which excess gases can escape. After formation, the
package is resealed to its final form, and the gas-bag is cut o ff. Nevertheless – more
than prismatic cells, pouch cells need careful temperature mana gement and support
structures when placed into a m odule. There are no standard siz es so far.

From Cell to Module and from Module to Pack

The wording “battery module” is usually only used associated with high -power
batteries. It denotes an assembly of cell packages, safety feat ures like temperature,
voltage and charge monitoring, as well as a battery management system (BMS),
cooling / heating system and a base plate or housing.
Depending on the capacity or voltage needs of an application, c ells are connected in
parallel or in series. Parallel configuration adds capacity, le aving the voltage constant,
serial configuration adds voltage, leaving the capacity constan t, respectively. Already
the electrochemical cell units in cell packs can be connected i n series (example: 9 Volt
“transistor radio” alkaline cell in Fig. 2 adding six 1.5 V AAAA-cell units, with
capacity approximately 0.5 Ah) or in parallel (example: 20 Ah L i-ion pouch cell for
automotive traction contains twe nty 1 Ah units, with external v oltage at around 3.6 V,
depending on cathode and anode chemistry [8]).
A comprehensive overview on battery safety features is listed i n [2]. Especially Li-
ion cell configurations must contain electronic safety circuitr y to prevent damage to
the user [7]. Since the overall capacity and voltage of a modul e are defined by the
weakest cell in the configuration, it is wise to monitor state of charge (SOC) and state
of health (SOH), amongst other parameters already on cell level . Battery Management
Systems provide this, combined with communication features to l evelize charging and
discharging, or even bypass bad cells. Tesla Motors, for exampl e, use standard 18650
cells for their modules and put all their efforts of optimizati on into the BMS, rather
than optimizing the cells [9, 10]. A BMS protects the battery b y preventing it from
running outside safe operation mode, such as over-current, over -voltage (during
charging), under-voltage (during discharging), over-heating, un der-cooling, or over-
pressure. It is therefore a very important part of the module.
The difference between module and battery pack is the individua l adoption to a
certain application. Table 1 shows typical requirements for a v ariety of applications.

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TABLE 1. Typical rechargeable battery app lications: different levels of energy and power
requirements set the scene for different cell chem istries and packaging (approximate values).
For comparison: A typical 18650 Li-ion cell approximately deliv ers 10 Wh.
Application Energy requirement [Wh] Critical system requirements
Smartphone 5 Energy density
Laptop PC 50…100 Energy density
Hybrid Electric Vehicle (HEV) 1,000 Power and lifetime.
Charging through recuperation,
0-5 km el. range
Plug-In Hybrid (PHEV) 5,000 … 10,000 Power and energy equally
important, lifetime. Charging
by grid and recuperation,
50-70 km el. range
Battery Electric Vehicle (BEV) 15,000 … 50.000 Energy, Depth of Discharge.
Charging mostly by grid, 100-
300 km el. range
Stationary battery buffering
residential photovoltaics (PV)
generator 5,000 … 10,000 Energy and lifetime. Average
household consumption per
day, charging by PV

Especially for large-scale appli cations (electric vehicles or r enewable energy
buffering) pack design is a differentiation factor for the batt ery integrators ( e.g. car
manufacturers). Therefore, standa rdization on battery pack leve l is hardly possible. On
module level, however, standardization can be beneficial, as sh own below.

PRODUCTION PROCESSES

Battery production starts with the preparation of raw materials , like the Li-metal-
oxides and graphite, which have to be thoroughly ground, mixed and conditioned.
Together with solvents they form a slurry of active material.
Second step is the electrode production , which involves coating of the active
material slurry on top of metal sheets in a roll-to-roll proces s, followed by drying and
compactation (called calendering).
The next step is the cell production . Slitting, separation, stacking or winding,
contacting of the electrochemical cell units, packaging are the single processes
employed here. Formation (initial charging) and ageing are impo rtant, but time
consuming steps (24 hours and up to a month, respectively) to f inalize cell production.
The last step in battery production is the module and pack assembly . Important
overall processes are inspection and test, clean room and dry room technologies, line
integration and automation.
The production of Li-ion batteries for high-power applications today is basically
low volume manufacture. Producers work hard on increasing yield s, reliability and
process stability. However, inspection and test for all critica l process steps are often
missing. A continous in-line operation is not realised yet, mos tly in cell production,
due to roll-to-roll processing. Full automation is not economic al as long as process
yield is still a challenge and the market does not demand huge volumes. VDMA has
set up a roadmapping process for the advancement of production solutions which
210

gives an insight to the state of the art, and future developmen ts in this field [11]. The
roadmapping process is still ongoing. The results will be publi shed elsewhere.
Although experience from the production of consumer batteries i s not completely
irrelevant to the production of t raction batteries, these two p roduct areas differ greatly
both in terms of quality and lifetime (significant reduction in fault rate) and the
production process itself ( e.g. much larger electrodes). That means that processes have
to be designed for manufacturability, i.e. higher precision, larger electrode areas, a
deeper understanding of critical parameters, measurement of tho se parameters, larger
process windows.
A unique case study revealing the impact of battery production advancements on
the production equipment industry has been made by [12]. Basic principles of
production, investment levels, and worldwide competition status have been indicated
there. Mixing and coating have been identified as the most rele vant process steps [12].
An even more detailed, very com prehensive overview on single pr ocess steps, process
data, critical process steps, key technologies and investement levels for machines and
equipment can be found in [13] for a Li-ion pouch cell, and in [14] for the assembly of
a battery pack. A video, which has been produce d by VDMA, also gives insights to all
battery production steps and chall enges for the machine makers [15].
Since this paper is aiming at the back-end of the process chain , we just refer to [12,
13] for details up to cell level.

Battery Module and Pack Assembly – Production Steps and
Challenges

Battery module and pack assembly brings up a number of challeng es: About 500
single parts have to be assembled in one battery system. There are e.g. 300 screw
connections and 200 –300 welding points to be set. The assembly of tubing and cover
plates can only be achieved manually. A special requirement is workplace safety: the
more cells are assembled, the higher the voltages that occur. A utomation is possible
for most of the process steps, but careful consideration if it pays off is needed.
Investment into automation also depends on regional specialties . Battery production is
still in an evolutionary phase (at least for high-power applica tions), i.e. requirements
for automated production rapidly change.
A graphical overview of typica l production steps based on pouch cells is given in
Fig. 5.

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FIGURE 5. Typical module and pack assembly today: Process steps, automat ion level today, and
voltage level for workplace safety. Example based on pouch cell s. *Cell Supervision Circuit (CSC).
Reprinted with permission of Klau s Schulz, Bosch Rexroth AG, an d [16].

Although highly desireable for cost-effective production, a lot of production steps
today still require manual handling, as indicated above. This i s partly due to the
precision required, partly a lack of measurement tecchnology, a nd partly an
economical issue. On top of the mechanical automation, there is still a lack of
automation on the information technology side, from data mining up to Manufacturing
Execution Systems (MES). To set up this line integration, conne cting single machines
to highly automated turn-key lines must be a goal for the entir e industry and poses a
huge opportunity to the production equipment makers in the medi um term [12].
Whereas clean room conditions and dry environment are an essent ial prerequisite in
electrode and cell production, it is workplace safety in module and pack assembly that
plays an important role for the production environment. Figure 5 clearly shows the
high voltages up to 600 Volts that occur during all assembly st eps.

212

TABLE 2. Overview of selected important process steps in module and pac k assembly, critical
factors and possible process solutions to cope with them. Compi led from [14, 16].
Process step and goal Critical factors and challenges Production solution
Cell sorting:
Precise handling x Pouch cells vary in form factor
and surface, surface is not stiff
x No alteration, puncture or
contamination of surface, low
contact pressure
x Tight fit and precise positioning x Complex gripping
technology, e.g. large area
vacuum gripper
x Reliable and fast handling,
stacking, supply of cells
x Powerful logistics systemc
Contacting of current
collectors x Lowest possible thermal load for
cell during process, fire hazard
x Biggest possible surface area for
weld x Ultrasonic welding
x Inspection of weld ed joint for
full functionality by voltage
test
Contacting of BMS and
sensor system (thermal and voltage sensors, sensor system readout) x Sensors are very damageable,
needs very high precision
x Danger of short-circiut by
inaccurate positioning of sensors
and printed circuit board x Soldering, ultrasonic welding
x High-precision handling
x High degree of automation
desireable
Assembly of housing,
insertion and fixation of modules, attachment of module connections x Screwing with high voltage on
x Chip formation, dang er of short
x Heavy loads
x Flexible cables are challenge for
automated handling x Sophisticated screwing
technology, manual screwers
with torque sensors,
automation with screw jacks
desireable
x Self-tapping screws
x Workplace safety
End-of-line test x Uniform charging and testing of
all cells
x Leak tightness test involves high
pressures, danger of burst x Ripple-free DC technology
with low voltage increase
x Sophisticated Measurement
and testing equipment
x Burst disk required

Table 2 gives an overview of selected important process steps i n module and pack
assembly, critical factors and possible process solutions to co pe with them. This
clearly shows that backend processes are far from being trivial .

COST CONSIDERATIONS

Cost is the important driver for the success of electromobility or storage for
renewable energy. Li-ion batteries for high-power applications are at a level of
750 US$/kWh today [18]. Price targets of around 250 €/ kWh to be met in the 2020
timeframe have been set, e.g. by the German government, several roadmaps and
independent studies [ e.g. 12, 17, 18, 19]. Cell production accounts for up to 50 % of
the cost of a battery today. Module and pack assembly still acc ount for around 15 % of
the total cost [12, 18]. This means that considerable cost redu ctions can be achieved
through improved production technologies – mainly through higher productivity and
yield. The leverage in this case is much bigger than in the raw materials part of the
process chain through changes of the cell chemistry. At the sam e time, it is necessary
213

to maintain the highest quality standards in order to avoid imp airing battery lifetime
and performance [12].
Only mass production will enable affordable solutions here. The investment in
production facilities involves ca. 200 million € for a complete cell line, the investment
into a battery packaging line is still at the level of 5 million € (basis: 10 million pouch
cells with 20 Ah) [13, 14]. Details for the investments in the individual process steps
can be found in [12, 13, 14]. With the market currently being s lower than expected,
manufacturers hesitate to heaviliy invest into new fabs. Howeve r, we believe that in
the medium term the market will see an upturn, at least for sta tionary storage. Annual
capital expenditure has been forecasted to almost 5 billion € in 2020 for traction
batteries alone [12]. Investment into stationary storage will p robably reach the same
amount or higher.
Compared to the cost of producti on equipment for semiconductors and flat panel
displays production facilities for battery cells are relatively inexpensive [12].

Best Practices from Semiconductors, Flat Panel Displays and
Photovoltaics

The learning curves in production of semiconductors, flat panel displays and solar
modules have shown significant cost degressions. In the semicon ductor industry, this
cost degression is also known as "Moore's Law". For DRAM, flat panel displays and
photovoltaic cells a doubling of production capacity leads to a cost reduction of 40 %,
35 % and 20 %, respectively. Important contributions to this ef fect were made by the
production equipment industry in f ields such as glass and wafer manufacturing,
coating technology, ovens, vacuum technology, handling, automat ion, laser
technology, the lamination of substrates and the soldering of c omponents.
Upscaling of pilot lines, timely introduction of alpha and beta tools following joint
roadmaps and the close collaboration between manufacturers and their suppliers have
made those industries very successful. Especially the roadmaps of the semiconductor
industry have almost reached the status of a “self fulfilling prophecy”, which easens
investment decisions. Success factors for the machine makers ar e to build consortia at
an early stage that are able to offer entire turn-key lines and have the ability to offer
technology packagings instead of just the bare machine. This wa y, the machine
makers can become drivers of innovation. A good example for thi s is the very
successful positioning of German photovoltaics machine makers o n the world market.
Electronics, flat panel displays , photovoltaics and battery pro duction employ
comparable processes: They all start with chemical processing ( e.g. electrode
materials, ultra-pure silicon or glass), involve coating large areas with high accuracy
(printing, PVD, CVD), require a high level of automation, utili se plastics (separators,
laminates, encapsulation), take place in clean rooms and need i nvestment in similar
orders of magnitude. Labour costs play a minor role. Innovation cycles are short. Last
but not least the products and therefore production are massive ly driven by cost.
Battery manufacturing can benefit greatly from the experience i n those related
industries. The experience of machine makers can pave the way t o highly automated
214

high-volume production of high-power batteries – and therefore make electromobility
and energy storage more affordable.

Module Standardization as Additional Path to Decrease Cost

One of the key questions behind an investment into high volume battery
manufacturing is to decide on a specific battery type. With the various chemistries,
shapes and sizes in which Li-ion batteries appear on the market , standardization seems
impossible. Small volumes in highly fragmented markets are hind ering scaling, and
thus the cost degression described above. On the module level t here have been
attempts to push for standardiza tion, described in detail in [2 0].
The idea behind it: A modular, standard, general-purpose batter y would tap
potential synergies across a big variety of applications. Clear ly defined external
dimensions and interfaces would facilitate universal deployment of modules in many
application areas. Different numbers of basic modules could be put together to supply
the power needed by each application. The large cumulative numb er of units could
thus cut costs significantly in many industries [20]. The study first looked into
different market segments, including mobile machinery, stationa ry storage for
residential PV, and recreational vehicles. In fact, mobile mach inery has a broader
installation base than batteries for electromnobility in the au tomotive sector. The
segments analyzed in this study altogether account for the thir d-largest block of sales
potential for all batteries, with a combined market volume of approximately 4 billion €
in 2020 [20].
The concept for a modular standard battery involves standardiza tion on the module
level. It is always based on the same core module in order to r ealize economies of
scale even for the most expensive components. The shape and che mistry of the battery
cell are not standardized, to enable cells from both the automo tive industry and other
sectors (such as power tools and consumer markets) to be used. Thus, competition for
powerful battery technologies, efficient production processes a nd innovative operator
models will be further intensified as a result [20].
Despite less differentiation capability relative to competitors , possibly accompanied
by thinner margins, battery manufacturers would clearly benefit from a broader
spectrum of customers, lower bill of materials due to economies of scale, optimized
set-up and cycle times, lower de velopment costs and higher inve stment security [20].
The overall effect for battery integrators and end users is cle arly an additional route to
cost reduction.

215

SUMMARY

Although the front end production steps (up to cell level) have the highest impact
on the characteristics and cost of a battery, back-end design a nd processes (packaging)
significantly influence its shape and performance. The packagin g adds important
safety and intelligent control features. Especially Li-ion batt eries would not be
manageable without them.
Packaging is divided into cell, module and pack level. On cell level, cylindrical
shapes have the longest history and are used for standard NiCd, NiMH, Li-Ion and
even lead-acid chemistries. Modern handheld devices, as well as automotive traction
applications have triggered prismatic and pouch types of cells.
High-volume mass production is already achieved for standard pr imary and
secondary consumer-type batteries, as well as for lead-acid sta rter applications.
However, improvements are still being made here, as cost pressu re continues. For
large-area, high-energy-type Li-ion batteries with big form fac tors there is a lot of
room for optimization, worldwide. For a fab, a number of altern ative processes and
process parameters have to be chosen. Inspection is crucial. Fu rthermore, automation
and line integration will greatly enhance yield, precision and workplace safety.
The experience made in the production of semiconductors, flat p anel displays and
photovoltaics can partly be adopted to battery production, sinc e a lot of major
characteristics for processes and ambient conditions are the sa me. Cost degression in
those related industries has proven to be steep and scales with increase of production
capacity. Machine makers can play a vital role in driving proce ss technology and
automation to the next level, using their experience from those industries.
However, the battery industry is stuck in small volumes in high ly fragmented
markets. This is hindering scaling, and thus the desired cost d egression. On the
module level there have been attempts to push for standardizati on, which would be a
benefit to all players along the value chain.

ACKNOWLEDGMENTS

The author gratefully acknowledges the assistance of the ESTORM team in
Freiberg and thanks the ESTORM committee for the opportunity to present this paper
at their conference.
I greatly appreciate the continuous support of my colleagues at VDMA for the
Battery Production Industry Group, especially that of Thilo Bro dtmann, Sarah
Michaelis and Sabine Egerer. Thanks to Bernhard Hagemann and hi s team at VDMA
Forum E-MOTIVE for investing a lot of work into the module stan dardization paper
together with Roland Berger, and his commitment for our work. M y deep gratitude to
the many company members of VDMA Battery Production for their i nterest in our
endeavour, which made the foundation of our industry group poss ible in the first
place. Thanks to our board for their commitment and guidance, e specially to Peter
Haan at Siemens Industry Group.
216

Special thanks to Heiner Heimes and his colleagues at WZL, RWTH Aachen for
the valuable partnership in our battery roadmapping working gro up and the
opportunity to get important insights to manufacturing cost wit h respect to our battery
manufacturing brochure. I am also very grateful to Klaus Schulz , Bosch Rexroth, for
sharing his slides on module manufacturing process steps. Last but not least thanks to
Andreas Gutsch, Competence-e, Karlsruhe Institute of Technology (KIT), for very
helpful discussions and the beneficial collaboration during the making of our industry
video and beyond.

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