Combining the high energy density of batteries with the high power density of ultracapacitors, provides a better power profile than either alone.
Maxwell Technologies and Tianjin Lishen Battery, hybrid describes a new sort of energy storage product that combines ultracapacitors with lithium-ion batteries. The two companies recently announced they would partner up to produce this hybrid power source, and samples should be available early next year, possibly in EVs.
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Ultra-capacitor/li-ion battery "hybrids" being developed in China - AutoblogGreen
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