Is a USB handwarmer safe (regarding fast battery discharging)?

[LEDrock]

After hearing about lithium batteries used in vaping devices exploding in the user's pocket, I thought it would be a good idea to ask about lithium batteries used in USB handwarmers, like this one: https://www.amazon.com/dp/B07H3LZGSP/?tag=cpf0b6-20

In order to create a good amount of heat, I imagine that it might be very demanding on the battery, just as vape products are. It's called a handwarmer, but I was thinking of just putting it down the front of my shirt with my shirt tucked in, and then it would be a body warmer. I used to do that with a charcoal stick powered warmer and it worked great that way. I wanted to do the same thing with this battery operated version, but the idea of an exploding lithium battery inside my shirt with no way to get it out quickly has me a bit worried. Should I be?

 

[3_gun]

Most of the vape issues I've heard the whole story on end up being user error. Wrong battery, damaged battery, damaged unit, etc. I'd guess & this is just a guess; if you follow the manufacturers recommendation & instructions on proper use you should be fine.

The greater the risk the closer I follow directions

 

[aznsx]

After hearing about lithium batteries used in vaping devices exploding in the user's pocket, I thought it would be a good idea to ask about lithium batteries used in USB handwarmers, like this one: https://www.amazon.com/dp/B07H3LZGSP/?tag=cpf0b6-20

In order to create a good amount of heat, I imagine that it might be very demanding on the battery, just as vape products are. It's called a handwarmer, but I was thinking of just putting it down the front of my shirt with my shirt tucked in, and then it would be a body warmer. I used to do that with a charcoal stick powered warmer and it worked great that way. I wanted to do the same thing with this battery operated version, but the idea of an exploding lithium battery inside my shirt with no way to get it out quickly has me a bit worried. Should I be?

I'd agree with 3_G for the most part, but would also try to go with a 'name brand' if possible with most anything lithium ion powered (which that one may be - I don't know). If I thought it was decent quality from a decent supplier, I'd go for it!

FYI - Used the old JonE type way back, and lots of folks used two in a belt like the one in this photo. Apparently having them at / near the kidneys was thought to be the ideal for maintaining core temp(?).

VTG JON-E HAND WARMER NOS JON-BELT JON-E BURNER 4 NOS PIC HAND WARMERS HONG KONG | eBay

HUNTING HAND WARMERS ,1 JON-E WITH BELT & EXTRA BURNER ,4 NEW OLD STOCK PIC. HAND WARMERS HONG KONG ,NICE LOT OF WARMERS . BOXES HAVE DIRT ,PAPER LOSS,TEARS WEAR USE ,REST OF LOT NEW OLD STOCK. SHIPPING INSIDE THE USA ONLY THANK YOU

www.ebay.com

 

[LEDrock]

I'd agree with 3_G for the most part, but would also try to go with a 'name brand' if possible with most anything lithium ion powered (which that one may be - I don't know). If I thought it was decent quality from a decent supplier, I'd go for it!

FYI - Used the old JonE type way back, and lots of folks used two in a belt like the one in this photo. Apparently having them at / near the kidneys was thought to be the ideal for maintaining core temp(?).

VTG JON-E HAND WARMER NOS JON-BELT JON-E BURNER 4 NOS PIC HAND WARMERS HONG KONG | eBay

HUNTING HAND WARMERS ,1 JON-E WITH BELT & EXTRA BURNER ,4 NEW OLD STOCK PIC. HAND WARMERS HONG KONG ,NICE LOT OF WARMERS . BOXES HAVE DIRT ,PAPER LOSS,TEARS WEAR USE ,REST OF LOT NEW OLD STOCK. SHIPPING INSIDE THE USA ONLY THANK YOU

www.ebay.com

I remember those. They were sold at the same time I got my charcoal stick version. I didn't get the JonE one because I was leery of using a liquid fuel. The solid charcoal fuel sticks seemed safer. Now I'm not sure they can be found anymore.
EDIT: I guess I only had to look. Amazon has the exact one I have from 40 years ago. They didn't change a thing about it, not even the color: https://www.amazon.com/dp/B00305KAUW/?tag=cpf0b6-20

 

[KITROBASKIN]

How about getting a quality flashlight hotrod and sticking that down your shirt on high mode? Seems like it should have a thermostat though.

 

[LEDrock]

How about getting a quality flashlight hotrod and sticking that down your shirt on high mode? Seems like it should have a thermostat though.

True about needing a thermostat. A flashlight's heat should also be exposed to the open air in order to not over-heat.

 

[staticx57]

This is one of those things that is perfectly safe if the manufacturer is trust worthy. Some back of the napkin math with some given values. Manufacturer states 5200 mAh capacity. Manufacturer states medium mode may be used up in as little as 4 hours. Now some math. 5200mAh/4h cancel units and divide 1300 mA or 1.3 amp draw. This is enough for around 400 lumens. Can make a guess and say high mode is twice it and that's only 2 amps. Really not that high of a draw at all. Perfectly safe for lithium ion, do you trust the manufacturer?

 

[LEDrock]

This is one of those things that is perfectly safe if the manufacturer is trust worthy. Some back of the napkin math with some given values. Manufacturer states 5200 mAh capacity. Manufacturer states medium mode may be used up in as little as 4 hours. Now some math. 5200mAh/4h cancel units and divide 1300 mA or 1.3 amp draw. This is enough for around 400 lumens. Can make a guess and say high mode is twice it and that's only 2 amps. Really not that high of a draw at all. Perfectly safe for lithium ion, do you trust the manufacturer?

 

[LEDrock]

Well, the manufacturer is Ocoopa, which I've never heard of before. However, the Amazon reviews seem really good, with quite a few people buying them. I'm 99.999% sure it's Chinese, but isn't everything?

 

[aznsx]

Well, the manufacturer is Ocoopa, which I've never heard of before. However, the Amazon reviews seem really good, with quite a few people buying them. I'm 99.999% sure it's Chinese, but isn't everything?

If you mean assembled on a production line there, probably. If you mean designed &/or sold &/or supported by a Chinese company, not necessarily. I'm not trying to be picky. Those last 3 things can be far more important than the first - in my experience. There may not be any 'hand warmers' that check any or all of those last 3 boxes though, although some power banks do. Try finding a proper charger for cylindrical lithium ion cells that meets any of those. I can't, and I'd pay good money for one.

Edit: Just as an example, I see Zippo sells a line of such things. U.S. based and owned forever, with a name brand reputation I'm sure they would not risk by putting their name on a shoddy product or one they haven't fully checked out and are ready to stand behind. That's one example of what I meant when I used the term 'name brand' earlier.

 

[Timothybil]

All of the rechargeable hand warmers I have seen would have bene lithium poly battery packs due to the configuration. I have never heard of anyone having problems with a lithium poly device due to the different formulation. (These are the same kind of batteries that re used in cell phones.)