Lithium has the highest electrochemical potential of any current batteries. Typically they produce a percell potential of between 2 and 5 volts. Their storage and power density features make them attractive for HEV applications where they are in trial development. Some believe that lithium-based batteries could be the key for HEVs to become a major market force in commercial vehicles. The common categories are cobalt based, lithium-ion (Li-On), and lithium-ion polymer (Li-Po).
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