Officially..if it is a CRV3 it is, by definition, a NON-rechargeable Lithium battery pack.
However..the CRV3 happens to be basically 2 AA batteries in a cartridge shell. There is no restriction on the use of the cartridge shell so some off-brand manufacturers have created a Ni-MH
version that happens to be shaped like a CRV3...so they called it a CRV3 rechargeable.
Any camera that uses CRV3 size could also use: Alkaline AA (not very good), AA NiMH rechargeables, AA lithium (last long, but disposable)