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Recharging Lithium Ion Batteries in Club Huts

Bob Mehew

Bob Mehew

Well-known member
I have just been asked about banning recharging of lithium ion batteries in club huts overnight. My first thought is whether there is sufficient incidence of such fires, despite the graphic tales which arise after one, to warrant such a ban. The available statistics do not pick out lithium ion battery fires but do list nearly 50% of fires in dwelling places as "Other/ Unspecified" which is not helpful. So two questions.

Does any one know of a club hut which has a rule about recharging lithium ion batteries (and if so what is it)?

And typically how long does it take to recharge a lithium ion battery used in caver's headlamps?

I am in the first instance after this data rather than a discussion on preventative / impact moderating measures. So please don't hijack the thread down that line. Or better still, create another thread.
 
Scurion manual suggest a 5 hour charge from empty. Using the officially sold charger. I cannot confirm as 1, don't let it drain completely and 2 generally leave it plugged in overnight.
 
Charge will depend on the size of the battery plus whatever charging rate, typically an overnight charge.

It might be worth considering making a dedicated charging bunker for li-ion/li-po cells to abate any fire risk
 
We are debating this as a (mountaineering) club currently and actually sorting the charging 'ban' conditions & wording out at a committee meeting this evening.

- All phones have Li-ion batteries. They are quite established technology, low incident rate, relatively small batteries and by their nature are often accompanied by their owner.
- We don't cave from our huts, so not much lamp charging, but think E-Bikes are our biggest risk. Folks don't want to leave them outside for security reasons. They can easily leave them on charge whilst everyone goes to the pub. There is risk of people buying cheaper, unregulated battery packs etc.
- We also have an issue with people charging electric cars with extension leads (often in an 'emergency'). This is a slightly different, but related risk.

Our discussions started because one of our members saw a similar debate in the Fell & Rock. Their rules are here, see 9) b) vii) :

 
Standard 18650 cells used in Fenix lamps and the like, 2400-3500mAh, typically charge at 750mA, so about 3-5hours.
 
I've seen the completely charred remains of a farmhouse (one of my wife's relatives) when an electric motorbike was left charging under the veranda (Australia).

Thankfully battery fires are uncommon but unlike a smouldering phone or torch that you might be able to chuck out of a window, when they're scaled up to motorbike and car they're pretty much unstoppable

Essex fire rescue on EV fires "Our preferred approach is to let them burn themselves out" (https://www.bbc.co.uk/news/uk-england-66866327.amp)

So probably this becoming topical for EVs and the like, is driving an abundance of caution for smaller batteries. Personally I charge batteries by the back door, although completely inconsistently I don't take the same with phones. (Li Polymer?)
 
Craven Pothole Club has a rule for the cottages "... the charging of mobile phones and electronic devices, including E-Cigarettes is not allowed in the bedrooms"
 
Counterpart is that a phone catching fire where people are is more likely to be discovered than one in a "remote" area of the hut - advise is also not to concentrate flammable items. Most huts allow non members to stay, so do need a policy for Li-ion (Li-po are supposedly lower risk), particularly electric bikes / vehicles being higher risk items:
www.britsafe.org

Lithium-ion batteries: a growing fire risk | British Safety Council

Lithium-ion batteries used to power equipment such as e-bikes and electric vehicles are increasingly linked to serious fires in workplaces and residential buildings, so it’s essential those in charge of such environments assess and control the risks.
www.britsafe.org www.britsafe.org
 
Each lithium cell has a small probability of catching fire from a manufacturing fault, or damage. The more cells there are, like in a dodgy ebike battery, then the higher the probability that one of them can catch fire. Charger design is important to for cell charging balance. Also, in a dodgy ebike battery pack, once one cell goes up, the fire spreads to its neighbours, so they all burn. A dozen caving lights and a dozen mobile phones on charge are going to be fewer cells than a dodgy eBay special ebike battery pack and they will be spread apart, so the risk of one setting off it's neighbours is lower.
If you are not going to go for an outright ban, I would look at mitigation. A charging area with smoke alarm. Fire resistant partitions between lamps on charge, an outhouse away from the main accommodation. A typical hut already has fire risks. Gas for cooking and solid fuel heating. Design and rules for use keep the risks under control. Alarms and evacuation plans help keep people safe if the mitigations fail.
Is this drive for a ban coming from members, or an insurance company?
 
The topic was raised by a member. The British Safety Council gives food for thought and certainly reminded me that the use of Lithium Ion cells is far more diverse than just lights. Thanks for the comments.
 
Bob Mehew said:
The topic was raised by a member. The British Safety Council gives food for thought and certainly reminded me that the use of Lithium Ion cells is far more diverse than just lights. Thanks for the comments.
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Apologies for going in to prevention and impact modification, which you asked us not to do! Any one with a vape in the hut will have a Lithium battery too. They might be only using them outside, but those batteries will be on their person/kit and may end up being recharged in the hut too.
 
wellyjen said:
Apologies for going in to prevention and impact modification, which you asked us not to do! Any one with a vape in the hut will have a Lithium battery too. They might be only using them outside, but those batteries will be on their person/kit and may end up being recharged in the hut too.
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Banning vapes from being inside huts would definitely get my vote
 
I would also guess that in terms of risk of using crappy batteries I’d rank it something like
1) vapes
2) e-bikes
3) headtorches
4) phones/laptops/tablets etc
 
mikem said:
Although e-bikes have more than one cell...
Click to expand...
Yeah guess I’m ranking it on a basis that generally e-bike batteries come as a pre-made product, whereas lots of vape things can just have any old 18650 (or similar) from eBay/amazon/wish plugged into it
 
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