Be careful… IIRC, DeWalt batteries actually rely on circuitry in the tools, and it’s possible for an old tool to over-discharge them and reduce their capacity pretty drastically. Specifically, it seems the “low voltage cutoff” lives in the tool for DeWalt (and Makita and Milwaukee I think), while Ridgid, Ryobi, and B&D have it in the battery. The two former are for backwards compatibility, and I think the latter because god knows what stupid garbage tools they’ll throw at the line next (though my B&D sander is… fine).
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…
@wjrii Thanks for the good information. I knew that PC NiCad tools had no communication to the battery, not sure about their newer LI ones. Regardless I find that the DW batt last so long on the PC tools that I always end up charging them when I think I should rather than when they actually need it. Rarely do they get down to 1 light, let alone full discharge As the PC tools die (which is taking a very long time, only 1 of 9 so far) going with DW brushless which have even better batt life.
Be careful… IIRC, DeWalt batteries actually rely on circuitry in the tools, and it’s possible for an old tool to over-discharge them and reduce their capacity pretty drastically. Specifically, it seems the “low voltage cutoff” lives in the tool for DeWalt (and Makita and Milwaukee I think), while Ridgid, Ryobi, and B&D have it in the battery. The two former are for backwards compatibility, and I think the latter because god knows what stupid garbage tools they’ll throw at the line next (though my B&D sander is… fine).
Yes, that’s the point. With an adapter the user must perform the low-volt-detection manually.
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…
@wjrii Thanks for the good information. I knew that PC NiCad tools had no communication to the battery, not sure about their newer LI ones. Regardless I find that the DW batt last so long on the PC tools that I always end up charging them when I think I should rather than when they actually need it. Rarely do they get down to 1 light, let alone full discharge As the PC tools die (which is taking a very long time, only 1 of 9 so far) going with DW brushless which have even better batt life.