Good but expired now, but still useful
Electrovaya – Overcoming the Carbon Conundrum One Step Above the Rest
https://batteryblog.ca/2010/08/overcoming-the-carbon-conundrum-one-step-above-the-rest/
https://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/PTO/srchnum.htm&r=1&f=G&l=50&s1=5721067.PN.&OS=PN/5721067&RS=PN/5721067