I meant a number of Li cells in series, but that may not fit the spaot where 2 9 volt batteries had been.

 

I meant a number of Li cells in series, but that may not fit the spaot where 2 9 volt batteries had been.

ya, limited to about 46Wx72Lx28D milimeters.

I guess that pack I linked is basically 3 cells in series, 3.7v x 3... I guess it's just how the lithiums are, 3.7v or multiples of... can't seem to find much else off sites like Amazon and AliExpress.

I'd say just make a new amp board while I'm at it but, would be nice to keep some of the original stuff.

 

Li-Ion cells are 3.7V when sold, in storage and when half-discharged. They are 4.2V when fully charged then three in series produce 12.6V. Amazon, AliExpress and ebay sell cheap junk that sometimes are fakes. A local hobby store sells good quality Li-PO battery cells in many sizes.