I'm planning to use my M18 batteries with a power distribution box that steps down from 18V to 12V for some LED lights in my enclosed trailer. This box has adjustable low voltage protection shutoff, and I'm wondering what the safest voltage setting would be to protect my M18 batteries—specifically the 5.0xc and 8.0HO models. Any advice? Thanks!
2 Answers
M18 batteries have 5 cells in series, and the minimum safe voltage is generally about 2.5V per cell. However, it's better not to go that low as it can damage the cells due to uneven voltage. I usually set mine at no lower than 15.5V to account for any differences between cells.
I believe the cutout for M18 batteries is around 16V, but it's been a while since I checked. To be sure, I suggest draining one of your batteries in a tool until it stops working, then measure the voltage to find out exactly what it drops to.
I've seen numbers ranging from 13.5V to 16V. I think I'll run my leaf blower battery down to check what it reads.
I just let my 5.0xc drain down with my leaf blower until it cut off, and it was at 14.9V, so I think a limit between 15V and 15.5V sounds good.