Is anyone here worried about having so many lithium cells charging/sitting in their homes? I must be paranoid because of the occasional videos I see on boards catching fire, but I feel like when I get my board finished, I might feel nervous about having a DIY battery pack charging at my place. Can someone talk some sense into me? I’ll probably only charge the board while I’m sitting next to it and have a fire extinguisher nearby. But the thought of having a fully charged battery on standby, ready for the next ride makes me nervous too.
Fully charged battery just sitting there shouldnt do anything. I never leave the house when charging just so if something happens I’m there to prevent further damage. Best thing is to charge in your garage or near a door that leads outside so if something happens you may have time to grab the board and toss outside or at least push it outside with a broom or a stick. This is not very common but it’s always best to be safe.
Generally it is a bad idea to have fully charged Lipos lying around for more than a day. They get bloaty and it damages their capacity.
‘Only the paranoid survive’ (in the news today but also seems relevant). I think the paranoia is mostly healthy. Also yea you don’t want to have fully charged stuff sitting around for an extended period of time really typically I will charge up a bit before I know I’m going to go ride for a while and usually that charge up is good enough for a few, few mile rides. Be aware fire extinguishers don’t really do anything to put out a lithium battery they just help you to keep things around it less on fire. It is a relatively rare thing to have happen and we have lithium batteries in our laptops and phones and we don’t ever think about them because the charge circuitry is conservative and has a lot of safety precautions built in. Problem is we’re dealing with a more raw version of the lithium batteries so it’s on us to either add safety measures (cell level fuses for example) and/or monitor and check things regularly to be sure nothing is showing signs of wear or damage.
Also linked this in the PSA thread but if you didn’t see it there https://www.youtube.com/watch?v=gobFcNzGG9I
Thanks for the link to the YouTube video. I like the battery charging bunker idea. I think I’ll set one of those up in my place somewhere I won’t have to look at it. The only other option I’ve seen are those FAA fire containment bags that are about $500. This should be great. I’ll pick up a bag of sand too. Hope never to have to use it, but at least I know that maybe if there was a fire when I am not home, that it could possibly even stay inside the concrete container.
No problem yeah the bunker is a pretty ideal solution. I made my lipos easily removable so I can just take them out to charge and check them out whenever I need to charge up and my new charger shows the internal resistance (IR) in milliohm per cell so can see how they are all doing which is a nice feature.
If you go lithium ion 18650 cells would just say go with a known good manufacturer for the battery and probably don’t go the DIY route or be ready to do a ton of research and testing.
I’ve dead shorted my lipos like 5 times yesterday and blown 2 connectors.
My mom walked in and I got distracted and connected a 10s lipo directly to a 5s lipo. Result: white smoke and burned connector.
Shorted another lipo due to exposed wires etc. I’m rewiring my whole battery and discharging it manually for storage. Bought 4 12v car bulbs. Cost me 20 bucks.
I’m not using a bms. My cells have a 0.01v per cell difference. Still got an intact house though.
Wire your setup correctly and make it robust. Vibrations get everything loose, trust me. Never had anything blow up due to charging. (Except 2 bms’s lol) Whatever you do, do not overcharge or overdischarge.
Okay end of horror story.
TL;DR Make sure your setup is robust and check every so often. You’ll be fine.
Jared (Jlabs) is building a 12s4p with BesTech BMS and 30q cells. I’m sure he builds great batteries, but I really don’t want to burn anything down, lol.
I wanted to also say that, I don’t want anyone to think that I’m doubting the quality of Jared’s work. It’s the abuse that a battery pack could go through while being attached to a skateboard that makes me a little nervous. I’ll be sure to pad it in the enclosure very well.
I sleep with my batteries. I discharge them under my blankets to keep warm.