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INDUSTRY VIEWPOINT: ALABC assembled and fully equipped with controllers and coolers battery. The difference depends first of all on battery chemistry. This is why only cells-to-cells or battery-to-battery comparisons can be made. The Ragone plot shown in the Encyclopedia of Electrochemical Power Sources offers two stripes for leadacid batteries placed in the low energy and low power areas. The values used for this plot describe relatively old battery designs. A look at the performance of the best battery designs developed by ALABC members shows that lead-acid batteries are advancing rapidly and are getting closer to the other widelyused chemistries (see figure 3 on previous page).

Future technical areas for ALABC To meet HEV requirements and maintain a position as the battery of choice, lead-acid batteries need to achieve higher values of their parameters, and the ALABC program is designed to support and accelerate this advancement. The key target parameters are: • Increasing charge acceptance and dynamic charge acceptance. Achieving this requires fundamental studies of crystal growth and mass transport within the active material; • Lowering cost and weight. This can be achieved by increasing the utilization efficiency of the active materials (lead, lead dioxide and sulfuric acid); • Migrating advanced HEV battery

Figure 4. Battery DCA, life and energy throughput in HEVs

Technology to industrial/storage/ non-automotive. These are high growth areas for rechargeable energy storage; and, • Rationalizing the demonstration projects. This means, joint development programs, trimming the fleet and moving to non-automotive

Major technical advancement targets: DCA and cycle life The electric energy used (discharge) in hybrids increases from 1 kWh in startstops to 10 and more kWh in plug-ins (average size vehicles). More brake energy needs to be used for recharge in more electrified vehicles, accordingly. The amount of energy flowing through the battery is also higher. (see figure 4). Advanced lead-acid batteries need to reach higher values of the DCA (up to 10 Ah/A and TET (up to 9,000 times Cn) till 2030 when start-stops and strong micro hybrids (full hybrids) will still have strong or dominating market positions until EVs and PHEVs take over. If the above values are not reached soon, lead-acid batteries could be pushed out by other chemistries. Once this happens, it will be very difficult to come back to this position. If lead-acid batteries reach these values, they will be able to minimize today’s performance gaps with competing chemistries (see plot below). In recent years, the ALABC program has shown that: • The UltraBattery can meet the needs of mild HEV duty (Civic Hybrid) for more than 150,000 miles. • Lead-carbon batteries are more than adequate for the 48V/12V operation in the LC SuperHybrid projects. • Further improvements to leadcarbon batteries may allow for use in full HEVs (the next targets may be in a Prius or possibly a low-end plug-in). • Based upon today’s DCA stability values of about 0.5 A/Ah (we already have members with up to 1.2 A/Ah, and we consider the limit of 1 A/Ah as a mass production possible value) and once the theory is ready and supported by matured technology, it will be possible to target 5 A/Ah by 2020 and 10 A/Ah by 2030. • The enhanced parameters will provide durable and lighter-weight batteries to the consumer.

Cost: What is the product designer trading-off? Figure 5. Energy throughtput and dynamic charge acceptance

18 • Batteries International • Fall 2014

Lead-acid batteries have four major

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