Power tool batteries as a 12V source for LED strip: yes or no?

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Power tool batteries as a 12V source for LED strip: yes or no? Anyone done it before? I’m exploring options to light my bike (headlamp, tail lights, LED strip).

I have a 3D printer and am prepared to sink some time into modelling an adapter to fit any battery which proves cost-effective.

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I have done it. Combine with a cheap buck converter for 5V or whatever. Pros: easy swappable battery pack with a fast charging station. Cons: They are almost never the cheapest way to get the same amount of mAh.

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I’ve found a couple of reputable sellers of lithium-ion batteries on AliExpress, one for plain cells and one for 18650s. They’re great value for money.

https://www.aliexpress.com/store/1191644?spm=a2g0s.13010208.99999999.341.5dGLaL

https://easylander.aliexpress.com/store/402603?spm=a2g0s.9042311.0.0.hoB4X9

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@Jeremy_Spencer , cheap cells from China always look good on paper, but they’re often over-rated, sometimes to double of the theoretical capacity of the cell chemistry (I guarantee you won’t find a “4200mAh” 18650 cell that can actually deliver as promised).

How much charge have you measured one of those cells as actually holding?

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@Luminous_Elements , you’re right there are loads of rubbish batteries out there. I bought samples from lots of suppliers and tested them before settling on these two.

I use the panasonic NCR18650Bs, they claim 3400mah. I have two different battery testers and they tend to hold about 3200mah.

https://www.aliexpress.com/store/group/For-Panasonic/1191644_260886538.html

I buy 1000mah cells from the other supplier, they measure up at about 950mah. I’ve just ordered some 2000mah cells and will see how they do…

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I cheap out on most things, but refuse to do so for two things: lithium batteries, and USB wall chargers. Both lessons learned by fire.

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I’ve got a bike project underway that will run at 12V native and draw well over 100W peak (:sunglasses:) and I’m still not sure what to use. Original plan was an LiFe RC car battery but the 8000mAh one in the Hobbyking catalog is a phantom, not actually buyable (at least in the EU.) Lead acid is too bulky. Custom means fire. Prebuilt UL-certified custom (from Batteryspace or similar) is expensive. I was thinking power tool packs might have a good combination of capacity and safety. Love to hear an experience report!