I have been looking at Sony VTC4 and 5 and the equivalent Panasonic batteries These cells are rated at 2.1 to 2.6 AH and have a maximum current rating of 20-30 amps. Each cell is about the size of a pencell and weighs 1.5 ounces. They are actually the same chemistry as our LIPOLy's that are not lipoly but LIFE. I made up an 8cell pack that weighs 12 oz producing 33 V. I plan to use this pack to power an aircraft.
I am using a two cell pack to power a late model ignition that is rated for 8V.
Since they are in an aluminum can they are safer than a LIPOLY. .
I got twelve off of ebay for $4 ea.
The MFG will not sell them individually. They are intended to be made up into laptop batteries so you have to rely on ebay. Beware of fakes!