Leaving rechargeable Li-Ion batteries in Lights

[LED-Wingnut]

Hey all. I've tried the search feature but didn't have much luck.

Here's my question: is it safe to leave a rechargeable Li-Ion battery inside the light for a longer period of time (say 6 months)? Regular batteries can leak and damage/ruin the light. Just curious if the Li-Ion type (18650, 18500, etc) type of batteries are prone to leak over time. Don't want to spend $100+ on a light to have it ruined from a leaky battery.

Thanks in advance for the responses.

 

[andrewnewman]

I've never had anything leak out of a Li-Ion cell except if it is physically damaged but I still would council against leaving them in a light for 6 months. Li-Ion cells suffer from a certain amount of self discharge (though not as much as some chemistries). This becomes more pronounced as the cell ages. Since they also don't like to spend long periods of time in a discharged state, you will probably want to pull them and top them off periodically.

I recommend storing Li-Ion batteries out of the flashlights and in plastic storage boxes in a cool spot. Some people refrigerate them.

If you want to store a flashlight for 6+ months and still be able to count on it, I recommend getting one that will take 1 or 2 CR123a lithium primary batteries. These will store for years without losing charge, don't leak and are very tolerant to a wide range of temperatures (though I would advise against storing them in a car in the summer regularly).

 

[SilverFox]

Hello LED-Wingnut,

Welcome to CPF.

Li-Ion cells don't leak like Alkaline cells do.

Tom

 

[march.brown]

My intention is to leave a 18650 torch in the glove compartment of the car all the time, so it is there for any emergencies ... Three of my 18650 torches also take a cassette containing three AAA batteries ... I can leave the cassette fitted with Eneloops in beside the torch as it is easy to take the 18650 out and pop the cassette in ... Though it would be just as easy to use another 18650 instead and have three times the battery life ... Sort of Belt-and-Braces so to speak ... My original intention was to recharge the cells before Winter set in, just so there would be fully charged batteries for the bad weather.

On reflection and after reading CPF, I would do the recharges twice a year instead ... This would take into account the car heating up in the Summer months ... Li-Ions will self-discharge quicker if the temperature is high but Winter temperatures pose no problem ... With the 18650s, it would be a simple check to measure the voltage with a DVM and if it was below say 3.9 volt then you would know that it was below 60% capacity ... You could set your own limit for required capacity ... On the other hand you could take a fully charged battery out to the car and swop them over ... Can't see any problem except for the Summer heat.

No need to spend $100 on a torch for the car ... The superb Solarforce L2 (18650) five mode is brilliant ... You could get four of them for your $100 ... I have two and they are my most expensive torches ... I also have a L2i which is a three AAA single mode version ... This is easily converted to take the 18650 which I have mentioned in another post.

I don't like the idea of a multiple (loose) battery torch as it is not so good trying to put more than one battery into a torch in the dark ... Of course you would still have your every-day-carry torch as back-up wouldn't you ?
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[LED-Wingnut]

Thanks for the replies. I'll probably not leave the Li-Ions in the lights for extented storage.