I also use Dewalt 20V tools. I have 2, 20V 5Ahr batteries and several I've bought from Amazon that are supposed to be compatible. I would really like to see the design used for your BMS. I have several drills with 20V 2.5 Ahr packs as well. My grandkids have 5 different Power Wheels ride on toys that I acquired with dead 12V batteries for either $25 or free from the trash. I changed the programming on one of my BLDC external controls so it operates like an H-bridge brush control. The switches on these toys simply reverse the polarity on the PM brush motors for reverse. With my control I can ramp up the acceleration and use a controlled reverse so it doesn't slam the gearbox. I use the 20V lithium packs on all of these and can adjust the top speed, typically a PWM at 20kHz that supplies 12V to the motors (I can crank it up to 20V, but they go too fast for the grandkids). It's really amazing how long they can ride on a small 5 Ahr pack!
On Tue, Oct 7, 2025 at 11:09 AM (-Phil-) via EV <[email protected]> wrote: > 2 things: Surprisingly most power tool batteries DO NOT BALANCE! I was > shocked to find this out. I bought into the DeWalt series, and I've always > treated my tool batteries very carefully, but when I tested, I found many > old packs wildly out of balance. The charger still senses the strings, so > nothing bad will happen other than shorter pack life. I've since built my > own DeWalt charger with balancing, and adjustable cutoff, so I can charge > to much lower voltages if desired (which I usually use). > > The other issue is, unless you get lucky like Bill, these packs are super > expensive for what they are! > > -Phil > > On Tue, Oct 7, 2025 at 6:52 AM Lee Hart via EV <[email protected]> wrote: > > > Bill Dube wrote: > > > Awhile back I adapted a ~40 volt Ryobi lawnmower battery to fit my > > eBike. Seems to work perfectly. > > > > A friend of mine did something similar. He converted a go-kart to EV with > > six 18v Ryobi battery packs, an Advanced DC motor, and golf cart > > controller. He opened the packs and bypassed the internal circuit breaker > > to get more current. My gawd the thing was fast! > > -- > > Excellence does not require perfection. -- Henry James > > But it *does* require attention to detail! -- Lee Hart > > -- > > Lee A. Hart https://www.sunrise-ev.com > > > > _______________________________________________ > > Address messages to [email protected] > > No other addresses in TO and CC fields > > HELP: http://www.evdl.org/help/ > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20251007/272c5e3e/attachment.htm > > > _______________________________________________ > Address messages to [email protected] > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20251008/5d132885/attachment.htm> _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
