On Thu, 19 Nov 2020 00:36:26 +0000, John Rumm
wrote:

snip

There will usually be a BMS in the pack on any respectable battery,
however some also communicate with the device - perhaps allowing the BMS
to instruct the tool to shut off or passing thermal data from the tool
to the batt (this is conjecture - I have not studied what passes on the
additional pinouts on the batteries)

I believe that to be the case on at least some of the Makita batteries
in that there is an external connection to the thermistor in the
battery that *could* be read by both the charger and / or tool.

Cheers, T i m