Maker
Most folk just call me; Orange Joe
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Cheap eBay bike light battery;
Just picked it up and the tab at the top started glowing and melted through the case (Heatshrunk black plastic). Brown pants moment as I sprinted outside with it. Once I was happy it wasn't gonna blow up (The tab acted as a fuse) I peeled the case off and found the cable all twisted, shorted, melted and burnt inside. That could have happened in my back pocket.
It seems its just down to poor mechanical design, there was no strain relief on the cable and with such an insubstantial case, the cells were able to move, allowing the nickel tabs to wear through the plastic around each cell and short out. There's protection ICs on the back side of that circuit board so it's not bad electrically speaking.
It was about £20 for the battery and a "7000" (Chinese) lumen light, I've had it ages and it was really good, could easily go hooning down trails in complete darkness with it. I might cut off the damaged cells and rebuild it as a 2S2P pack, probably buy a new one too, unfortunately my budget won't stretch to a non-Chinesium one.
The first few times I charged it I used to sit it in a stainless bucket but eventually decided it was safe, I might get one of those proper LiPo charging bags now.
Just picked it up and the tab at the top started glowing and melted through the case (Heatshrunk black plastic). Brown pants moment as I sprinted outside with it. Once I was happy it wasn't gonna blow up (The tab acted as a fuse) I peeled the case off and found the cable all twisted, shorted, melted and burnt inside. That could have happened in my back pocket.
It seems its just down to poor mechanical design, there was no strain relief on the cable and with such an insubstantial case, the cells were able to move, allowing the nickel tabs to wear through the plastic around each cell and short out. There's protection ICs on the back side of that circuit board so it's not bad electrically speaking.
It was about £20 for the battery and a "7000" (Chinese) lumen light, I've had it ages and it was really good, could easily go hooning down trails in complete darkness with it. I might cut off the damaged cells and rebuild it as a 2S2P pack, probably buy a new one too, unfortunately my budget won't stretch to a non-Chinesium one.
The first few times I charged it I used to sit it in a stainless bucket but eventually decided it was safe, I might get one of those proper LiPo charging bags now.