Page 73 - Energize July 2022

TECHNICAL

procedures) in order to secure the future of lithium-based energy storage. the limitations of maximum depth of
Further, it is very challenging to define one single basis for the recycling process due discharge, lead-acid can still be considered
to the different cell chemistries of Li-ion cells. In each case an individual solution has to a good alternative with a faster breakeven
be agreed upon between the customer and recycling partner (see Figure 10), to find a scenario when looked at as a business
reasonable recycling process that focuses on the materials requirements while at the end case for cost purposes.
reduces the price for the processing.
References
Summary 1. Jim McDowall: “Sophistication
Tables 1 and 2 provide a comparison of the advantages and disadvantages of both battery versus Simplicity – System Design
types for commercial and industrial applications (excluding consumer electronics). Considerations for Li-ion Batteries in
Standby Power Applications”, Battcon
Conclusion Proceedings, 2010.
Li-ion technology is certainly a well-established technology for mobile technology including 2. Peter Birke and Michael Schiemann:
EV and PHEV/REHEV. It now seeks to enter the market for traditional standby industrial “Akkumulatoren: Vergangenheit,
applications, driven in large part as a means to recover the very large investments made in Gegenwart und Zukunft
plant infrastructure. Elektrochemischer Energiespeicher,”
However, for traditional standby applications with a moderate cycle requirement, Herbert Utz Verlag, München, 2013.
lead-acid batteries remain a highly effective cost-benefit solution, especially for sites 3. Jeff Dahn: “Li-ion Batteries”, Linden’s
where installation space is not a major limitation or where high volume is not required for Handbook of Batteries Technology, 4th
discharges at the mains. Lead-acid is a proven system with over 100 years of evolutionary edition, 2011.
experience and their initial installation costs are reasonable. 4. Doron Aurbach and Bruno van
For applications where a high daily energy throughput is needed, and duration periods Schalkwijk: “Advances in Lithium-ion-
are not excessive, Li-ion technology can exist on a par with lead-acid batteries. For home Batteries”, Kluwer Academic / Plenum
solar systems, it can be a very effective alternative. For industrial applications, however, Publishers, 2002.
like behind-the-meter systems in hospitals, universities and business parks, as well as for 5. Ralph Brodd, et al: “Li-ion Batteries“,
electric utility protection and control systems, lead-acid is still a most attractive and very Springer, 2009.
cost-effective solution.
For smart grid and utility-scale applications, opinions are divided. Both types of Contact Clive Rutter, Silicon Engineering,
batteries are in various stages of pilot or commercial operation. Attention will continue Phone 011 474-3423, clive@silicon.co.za,
to focus on improving the predicted lifetimes for Li-ion technologies. However, even with www.silicon-online.co.za

ADVANTAGES DISADVANTAGES
Lead-Acid Batteries Lead-Acid Batteries

• Proven technology – over 100 years • Maintenance required to ensure batteries perform to
• Cost-effective for traditional standby applications expected life
• Ease of installation - no battery management control system required • Requires more floor space to install an equivalent Ah or kWh
• Good cycle count with tubular and gelled-electrolyte cells Li-Ion string
• Published standards and best practices exist
Table 1: Comparison of advantages and disadvantages of lead-acid cells
ADVANTAGES DISADVANTAGES

Li-Ion Batteries Li-Ion Batteries

• No manual maintenance required • No manual maintenance permitted – requires Battery
• Good cycling life – discharges up to 100% of capacity; 4000 cycles Management Systems (BMS)
with Li-Ion designs • Safety concerns: fires and thermal runaway – includes capacity
• High specific energy and energy density loss and potential for thermal runaway when overcharged
• High rate discharge capability • Higher initial cost for traditional standby applications
• Low self-discharge rate • Degrades at high temperature
• Fast recharge capability • Becomes unsafe in extreme cold temperatures
• Additional effort for recycling necessary
• Relatively new in industrial standby applications – technology is
less than 25-years old
• No solution yet regarding damaged batteries (electrolyte
leakage)
• Published safety standards and best practice guidelines do not
currently exist
Table 2: Comparison of advantages and disadvantages of Li-ion cells

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