Here's a "safety share". Be careful charging LiFePO4 batteries in a closed environment. I had a disturbing reaction to what I now think was off-gassing from a LFP battery I was charging ten feet from my desk. The battery was 12V 8p 4s 100Ah made in China from cylindrical cells in shrink wrap, so I could not inspect them directly. Charging at 20 amps (0.2 C) for about one hour when I felt symptoms. I lost my sense of smell and felt a suffocating numbness in my nasal passages. I quickly went outdoors and stood in the wind for a few minutes, and a sense of normality started to return. When I went back in, and near the battery, the loss of smell returned. I immediately moved the battery outdoors and let it finish charging. I opened all doors and windows and let the wind exchange all the air in my house. After about 20 minutes my sense of smell returned to normal. I looked up the MSDS for LiFePO4 batteries and this line seemed to explain what happened: "• Inhalation: The steam of the electrolyte has an anesthesia action and stimulates a respiratory tract." Has anyone else run into anything similar to this?
Safety - bad reaction to off gassing, charging LiFePO4 battery
- Thread starter Nevadageo
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pablo fiasco
New Member
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Never heard of such a thing. Sounds like your batteries are not enclosed in a black case like most end user products. I wonder if your experience would be likely with a more typical consumer product. I always thot the absence of gassing off was one of the lithium advantages.
I always thought so, too. That's why I shared my experience. I suspect a defect permitting a gas leak. I plan to tear-down the batteries to learn what I can.
LeRoy Christensen
Laser Dude
We have mounted our Chinese 24v 400ah SinoPoly cells in our motorhomes bedroom. Have not started traveling yet in this new configuration but have noticed a slight metallic smell during charging and resulting bad headache while working in the bedroom. So they do gas off, with what I'm not sure. Is this harmful over the long-term? I hope not since they are mounted in very small sleeping space. Anybody know what chemicals LiFePo4 batteries emit?
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Ampster
Renewable Energy Hobbyist
Yes, ten years ago I had a similar situation with some Headways cylindrical cells that I was using on an ebike. The smell was like Ether which was a common Anesthesia chemical. I think my off gassing occurred as a result of over discharging the cells. It was my first experience with LFP cells and I don;t think I was even using a BMS, After that I was more careful and installed a BMS.
LeRoy Christensen
Laser Dude
We charge at maximum of 100 amps, but discharge around 300 +. Batteries are balanced by two different type active and passive. Sandwiched between 1 1/4" t&g flooring to prevent expansion. So any pressure inside Batteries are forced to vent.
OnTheRoadAgain
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I don't know about LiFePO4 batteries, but I do recall Lithium Ion batteries produce a toxic gas when overcharged.
It can be lethal IIRC.
I'm thinking LiFePO4 batteries have an entirely different, non toxic chemistry ?
It can be lethal IIRC.
I'm thinking LiFePO4 batteries have an entirely different, non toxic chemistry ?
Toxicity was discussed in this thread but this involved a cell that leaked. I am far from having any knowledge on this except I don't know of many reports of cells gassing. There was a time I thought mine were but it ended up being the smelly PVC tubing I installed around the threaded rods.
Perhaps relieving compression would put an end to it? I don't think gassing is normal. This is very concerning and it's my understanding the gas is extremely flammable. Did you read the posts from the guy that had a fire in his van? Maybe one of his cells was gassing and between that and a bad connection caused the fire. Of course I am speculating and we never will know what the cause was. The point is if cell(s) are gassing I would try to find the cell that's gassing and I wouldn't know where to start. It does need to be addressed.
