I found out somewhat recently that those Nokia batteries (like BL-5C) are still used in hardware. You can still pick them up on some stores.

I came across them in portable radios (portable FM radios, small global radios, plane listening radios and similar).

The N95 had something like 995 mAh. A modern iphone would have about 4x that.

Also interesting to know is that BYD was supplying a lot of phone batteries back then. I think they also supplied to Nokia. Phone batteries is what made them big.