Ford's CEO Mulally Launches New Electric Car Era with a Kiss

Looks like the Focus uses lithium polymer cells:
http://www.compactpower.com/bpack.shtml

Lithium Polymer, yes. Specific chemistry is Lithium Manganese, the electrolyte designation is that it is a polymer. The chemistry can vary. Typically it is Cobalt-cathodes, in the case of LG Chem it isn't.

The cathode material of LG Chem/CPI cells is explained on their site here, also with a description of their federal contract with US Advanced Battery Consortium.
http://www.compactpower.com/Documents/DOE_USABC_Agreement_FINAL.pdf

Cathode specific reference from that site

1) Safer chemistry (without compromises in performance or life) - specifically LG Chem/CPI use manganese-based cathode chemistry with additives to improve calendar life under high temperature conditions

Click to expand...

Improved calendar life, a must have in the Lithium battery industry.