explosion when charging li-ion cell, Universal Smart charger set on wrong voltage

[SilverFox]

Re: A Cautionary Tale

Hello David,

Sorry for any confusion...

Here is what mine looks like. This is an improved model that automatically selects the the number of cells. Mine has a slider switch that requires you to do this manually.

Mine is also different in that it charges at 500 mA.

It actually does a good job of charging, but you have to remember to set the right cell count.

Tom

 

[Bob_G]

Re: A Cautionary Tale

Barton,

This pdf is a fun, easy read to see how people for whom these things are important view them. It looks like overcharging is the main concern. It says there's a chemical released that reacts with water to form HF, but that's as far as it goes. Chemical reactions happen so fast, and are self perpetuating to some extent, forming new molecules that then have their own reactions and such, that I hope someone that understands chemistry well enough will answer your question

 

[cy]

Re: A Cautionary Tale

IMHO this charger should not be sold without proper warnings. ALL owners of this charger should be warned. especially now that real dangers of using is documented.

there's a 99% chance of someone using the wrong setting at some point.

Pila's will self terminate a charge. otherwise bare li-ion cell will accept current for long as you deliver it. li-ion cells when overcharged above 4.35 volts? or so may go into thermal runaway. at that point PTC shutting down 500 milliamps will do little to stop venting with flames.

http://www.calcars.org/calcars-news/521.html

This morning without thinking I put a 14500 on to charge (universal smart charger), I didn't check the switch setting, I was going about my business in the office when there was a very loud explosion, about as loud as a large fire cracker, I smelt carpet burning and my wife came into see if I was still alive. I had without thinking put the battery on to charge with the charger set to the two cell setting. Right now I'm about halfway through cleaning up the mess, the batteries internals were spread all over the room. The battery must have ruptured at the positive end as the wall in that direction is just covered with black crap, the battery casing took off in the negative facing direction leaving quite a dent in the wall..


Burnt carpet

The battery was sitting on another charger

Some of the black crap

Dent in the wall

 

[Norm]

Re: A Cautionary Tale

title needs to changed to reflect exact charger responsible for this failure. other owners and seller of this exact charger needs to be warned.

Title changed at Cy's request.
Norm

 

[Lips]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Charger

QUOTE=cy

don't think protected cell will help. since current is delivered at low current (500 milliamps?) depending upon cell, it may have high current discharge, low voltage and high temp (PTC) protection.


Pila's are the only exception I'm aware of that will self terminate a charge. otherwise li-ion cell will accept current for long as you deliver it. li-ion cells when overcharged above 4.75 volts? or so may go into thermal runaway. at that point PTC shutting down 500 milliamps will do little to stop venting with flames.

3rd attemp to post


This charger is sold at most of the battery e-stores I've seen online with a warning to put a protection circuit on the battery before charging. Most people probably gloss over it like I did. I use it about every day but it's a good thing to point out to new users to be carefull with unprotected batteries. (All batteries!)


I did a test with AW's newest protected bateries.

1 x 3.7v RCR123


Set the charger to 8.4v


Red light came on for two seconds and then turned green. The cells protection must have kicked in because the charger would not charge the cell past the current voltage (My Results Only…)


An unprotected cell I did the other day went to 4.36v where I manually stopped the charge…


Cheers

 

[cy]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

lips, great info!

seems AW's new protected R123 cells have overcharge protection too.
so far pila's and this new gen AW protected cell has overcharge protection built in.

does anyone else know if any other protected li-ion cells with built in overcharge protection?

I still maintain ALL purchasers of this Universal Smart Charger with manual switch needs to be warned of dangers of charging with wrong voltage setting.

can you post a link to seller with this exact charger?

 

[cy]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

sure wonder if current cpf buyers of this same "intelligent" charger know of this thread?

Norm, is this the charger that caused fire in this thread?
http://candlepowerforums.com/vb/showthread.php?t=117653

 

[dca2]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

sure wonder if current cpf buyers of this same "intelligent" charger know of this thread?

Norm, is this the charger that caused fire in this thread?
http://candlepowerforums.com/vb/showthread.php?t=117653

I have that charger (mine has the inline fuse) and use it to charge my Mag85 battery pack. I have 9 unprotected 14500's in 3 series of 3. Tell me if my math is right--that equals 11.1v so I should have it set to 12.6v, the third setting? It is on my desk at school and I don't really want to blow up the 7th graders in the front row--might move it to the back row where all the bad kids sit.

Dave

 

[ProofTech]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

lips, great info!

seems AW's new protected R123 cells have overcharge protection too.
so far pila's and this new gen AW protected cell has overcharge protection built in.

does anyone else know if any other protected li-ion cells with built in overcharge protection?

Wolf Eyes cells have overcharge protection.

 

[LuxLuthor]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

I sent Alin a PM since it is his GB thread....about reading this thread. If I posted a link to this in his GB thread, I would have another 20 million lemmings starting another jeers thread for me trying to be helpful.

 

[LuxLuthor]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

I have that charger (mine has the inline fuse) and use it to charge my Mag85 battery pack. I have 9 unprotected 14500's in 3 series of 3. Tell me if my math is right--that equals 11.1v so I should have it set to 12.6v, the third setting?

That is correct....but I still think it is crazy to put this in a classroom...especially using unprotected cells.

 

[dca2]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

That is correct....but I still think it is crazy to put this in a classroom...especially using unprotected cells.

Find the humor Lux, :nana: I know you posted after midnight

 

[cy]

explosion occurred, charging li-ion cell w/ Universal Smart charger on wrong voltage

title of this thread needs to be changed to reflect what actually happen. which is:

explosion occurred when charging li-ion cell with Universal Smart charger on wrong voltage setting

 

[LuxLuthor]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

Check out the actual videos I just posted in the other thread showing how deadly these batteries can be....and basically if it catches fire in a pack which is what I have been using my universal charger for, each cell rupture/fire gets worse than the last. Basically, one of these types of fires shown in videos will take down your home.

I honestly did not fully understand the dangers, and how to properly charge my Li-Ion batteries and packs until reading for several hours on the RC forums, and seeing these videos. IMHO, Alin should pull this Lithium charger for all the reasons I posted about in this post.

I have seen too many questions about what people should be setting it on when having various packs (typically FM's) in parallel or serial, such as this light with 2-P of 4-S.

I also just realized tonight that there is no way to load balance the typical FM battery packs, because in typical Radio Controlled Lipo packs, they have a "tap" wire separately connected to each cell in the pack...which gives the capability to individually monitored and charge with specific voltage delivered to each cell in case one has a higher Voltage than another.

In Alins' setup...or even using a Schultze or my Hyperion charger applied to the same FiveMega pack, they also have no way to determine if one cell has a lower voltage, and another one higher....leading to a low overall pack voltage....and over applying charge to that already high voltage cell.

 

[Norm]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Charger

I agree with LuxLuthor, after the accident I had, I'm sure that if you left one of these chargers unattended and set incorrectly you could easily burn your house down. I haven't used this charger again.
Norm

 

[cy]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

since you are the originator of this thread and only you can edit the title.

currently it reads just to take extra care when using this "smart" charger.

"explosion occurred when charging li-ion cell with Universal Smart charger on wrong voltage setting"

is above more accurate?

"Dumb" charger is more like it, if this charger can burn down your house with wrong voltage setting.

a lot of folks only read the title and don't realize what's actually happened.

don't get me wrong you can also cause li-ion cells to overcharge with other chargers, (leading to venting with flames) but there are safeties built-in to notify you a setting is wrong.

I agree with LuxLuthor, after the accident I had, I'm sure that if you left one of these chargers unattended and set incorrectly you could easily burn your house down. I haven't used this charger again.
Norm

 

[Brum]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

since you are the originator of this thread and only you can edit the title.

currently it reads just to take extra care when using this "smart" charger.

"explosion occurred when charging li-ion cell with Universal Smart charger on wrong voltage setting"

is above more accurate?

"Dumb" charger is more like it, if this charger can burn down your house with wrong voltage setting.

a lot of folks only read the title and don't realize what's actually happened.

don't get me wrong you can also cause li-ion cells to overcharge with other chargers, (leading to venting with flames) but there are safeties built-in to notify you a setting is wrong.

I'm using a similar charger I purchased trough ebay with two DIY Li-ion (with prot PCB) packs. No problems whatsoever, this charger is meant to charge PACKS and the user should make sure every pack he has is properly protected. Even if it has a single cell setting, this is meant for packs (or a single cell) in parralel, which also should have protection. I don't really get the commotion (well, not completely, you guys do have a point), if you use common sense and the necessary precautions nothing will happen. If you really dont trust it, just charge the cells somewhere outside inside a metal container.

 

[LuxLuthor]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

I'm using a similar charger I purchased trough ebay with two DIY Li-ion (with prot PCB) packs. No problems whatsoever, this charger is meant to charge PACKS and the user should make sure every pack he has is properly protected. Even if it has a single cell setting, this is meant for packs (or a single cell) in parralel, which also should have protection. I don't really get the commotion (well, not completely, you guys do have a point), if you use common sense and the necessary precautions nothing will happen. If you really dont trust it, just charge the cells somewhere outside inside a metal container.

That is exactly the problem....people don't "get the commotion," and assume that using it to charge a Lithium battery pack that does not read the individual cell voltages is perfectly fine. It is not fine, nor is it safe.

I also do not believe the added battery cell protection circuit gives adequate protection, given the magnitude of damage that can be caused by these cells. Watch the videos to see how violent and dangerous the explosions are. Has anyone looked at these battery protection circuits if the battery is dropped, or over-tightened and perhaps crushed in a FM type battery pack? Have they been tested for possible shorts developing from a multitude of causes?

On top of the inherent battery risk, this charger in particular is very poorly designed, given the danger of Lithium explosion fires. Look at the more detailed image where the cell selection switch numbers are very small and hard to read, and there is not a distinctive slot with the slider to make sure you are on the correct number of cells. With the added list of battery cell voltage to the left, it is a confusing and dangerous charger.



At the likely risk of getting a JEER against me, I just posted a warning about these chargers in Alin's GB thread. I realize some people will be upset, but I see this as a matter of public safety.



.

 

[Rommul]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

Big thanks to Norm for making the unaware, aware of the safety issues surrounding unprotected lithium ion batteries. There are safe procedures that must be taken with ALL these cells no matter the capacity. Much respect to Norm for being clear that he set the charger incorrectly, we all could learn from that.

But frankly I dislike the tone this very informative thread has taken on. I think people are now starting to use this thread to settle personal scores and malign certain posters. It really leaves a bad taste in my mouth.

CPF (unlike a few forums I frequent) is filled with such wonderfully helpful and well intentioned people. Its such a turnoff to see such pettiness on the part of a few ruin the experience. Its so sad to see posters pretend they don't know what is being discussed (asking questions they already know the answer to) in order to hide their intentions.

I hate to see this side of CPF.

 

[Rommul]

Re: Extra care required when using the Multicurrent Lithium Universal Fast Smart Char

BTW has anyone had this charger malfunction at all when it was properly used?