AJH wrote:

I thought the advantage of Makita cordeless tools was that they all
shared the same battery type yet when I was presented with a Makita
BUC122 chainsaw with no battery I couldn't fit the one from a drill, it
seemed to start sliding in but then reached a hard stop. Are there
different types of Makita 18V battery fittings?

ish ...

https://www.toolstop.co.uk/blog/knowledge-base/makita-18v-tools-and-the-batteries-that-power-them