A Quick Look at all the price drops on battery operated tools for this Black Friday seems to confirm a drop in battery prices.

Heaps of kits and the more basic skins (eg. leafblower, angle grinder, hammer drill) get massive discounts because they get people into an ecosystem (and once they’re in, they’re unlikely to move out). Black Friday SKUs are basically loss-leaders to sell the rest of the range (and extra batteries) at full price later on, so I wouldn’t use them to gauge the broader market.