Lipo and Lifepo are different battery tech. Far more volaiile, explosive and energy dense. They produce much more power than AA.

This page has 3.2v and 1.2v...you would need half the amount of AA with the 3.2v to avoid over volting it (although I expect you could run a bit more than the 1.5v that the system uses a multiple of.


https://www.batteriesplus.co.uk/acat...SABEgLLOPD_BwE

Also see the NIMH rechargeable ones.

If you can fit a lipo in the hole you would have all the voltage and tiny battery. Things like Radio controlled helicopters run on LIPO power.

A Tesla electric car runs on something like Lifepo.


The ones in this link are half the size of AA and twice the power so you would get 4 X AA voltage within the space of 1 AA battery

https://www.tlc-direct.co.uk/Product...SABEgI1r_D_BwE