(for various reasons I needed to join a mismatched pair of 18v drill and battery, annoyed at how much fun it was)

  • dual_sport_dork 🐧🗡️@lemmy.world
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    3 months ago

    FWIW, my Makita drill (18v) definitely has the BMS in the battery pack. I have two packs that came with my drill and I have re-celled both of them with fresh 18650’s, so I was in there to take a look. I’ve had the drill itself apart, too – there are no smarts whatsoever in there. I don’t have any other tools in the line, though, just their basic drill.

    What’s astounding to me is that there is no provision whatsoever for balance charging or individual cell monitoring. The packs are a 5S configuration and treat the entire series lump of cells as a single whole. If one of your cells shorts the BMS will never know and your pack will just go off bang. Maybe it’ll trigger the low voltage cutoff first if you’re lucky…