Lithium batteries going wrong

Some chemists at Cambridge University have come up with a theory as to why lithium cells sometimes go boom. I can't get access to the linked article from here, but may be able to at work.

Here's the abstract from:

Lithium metal has the highest volumetric and gravimetric energy density of all negative-electrode materials when used as an electrode material in a lithium rechargeable battery. However, the formation of lithium dendrites and/or ‘moss’ on the metal electrode surface can lead to short circuits following several electrochemical charge–discharge cycles, particularly at high rates, rendering this class of batteries potentially unsafe and unusable owing to the risk of fire and explosion. Many recent investigations have focused on the development of methods to prevent moss/dendrite formation. In parallel, it is important to quantify Li-moss formation, to identify the conditions under which it forms. Although optical and electron microscopy can visually monitor the morphology of the lithium-electrode surface and hence the moss formation, such methods are not well suited for quantitative studies. Here we report the use of in situ NMR spectroscopy, to provide time-resolved, quantitative information about the nature of the metallic lithium deposited on lithium-metal electrodes.

Now that was a good read........

My first degree was in chemistry which is why I'd like to see the full paper. Even if I am nearly 30 years out of date (Graduated 1982) I could probably figure it out. The Register is usually a good read and they don't mess up techincal stuff the way many journalists do.

What the abstract says, in summary, is that they used an MRI machine to directly image the formation of lithium metal inside the cell. Metallic lithium formation inside a cell is bad.

Anyone who's worked with datacentre installations of computers will have stories about zinc dendrites (whiskers) doing terrible things too. These come from the galvanised steel that most of the metalwork is made from.

Very interresting. But have they a solution to how we avoid the problem, except using protected batteries of cource?

Once they have a better idea of how the lithium metal dendrites get formed, it may be possible to change the formulation in such a way as to minimise their appearance and growth such that the lithium cobalt oxide chemistry (which is the highest capacity available at present) is considerably safer than at present. Meanwhile the trick is not to abuse them - don't try to charge them if they have dropped below about 2.5V after resting, don't batter them and don't charge them at high currents.

I have a dead lithium battery for my camera. Shows 0 volt. I have tried the supplied charger. No luck.

I have also tried with a laboratory power supply (nothing exploded), but still no result.

Any way to revive it?

Probably not. Sily question, it is a rechargeable cell/battery?

Assuming it has a nominal voltage of 3.7 - 4V it is a single lithium ion cell - if it is 7.2-8 it is a two cell battery.

Try putting about 20mA into it (With the battery in a fireproof container) at a bit over the rated voltage (nominal voltage 3.6V I'd not go above 5V, nominal voltage 7.2V 9-10V maximum) - just ramp up the voltage till you see 20mA flowing. Let it run for a few hours. The battery may well have an internal protection circuit that permanently shuts it down for safety. It might be possible to bypass the protection circuit but it is there for a good reason. If it is reading 0 volts I'd suspect a protection circuit has shut it down. Probably because one or more cells is in a bad way.

Thanks. Its a 3,6 volt Li-on to a Panasonic Camera. It said 3500 mAh. The stock battery is 900 mAh.

I bought it recently in Singapore. The high capasity wondered me, but as it would be nice with that,

I bought it. Maybe I have been cheated. He knew I was from Europe, so I probably wouldn´t be back

at the double to wring my hands around his neck when I found out.

It sat on the camera for some time, so I think your right about the protection.

I may try your solution some day. Outside wearing full protection suit!!

That's a pain about the battery. Probably toast - the mAh rating does sound suspicious unless it is 4x the size of the official one. If it wasn't expensive I'd just toss it.

I´ll toss it. He can just wait to I get back to Singapore some day!

Don are you still for the full text? I could help if you are...

If you could please, I'd really appreciate it. My academic account gets me biomedical stuff and sociological stuff, not interesting stuff.

Slightly OT but hey since this concerns li-ions exploding, if anyone missed it, someone had the unfortunate experience of batteries exploding inside their flashlight as reported in a German site and described/discussed on CPF

From an automatic translation "My right thumb was open to the bone"

Scary stuff!

Oh man yes it is......i always tell new comers that come into this hobby and really want to go lithium because of its energy density, lightness of the cell, and of course the power the cell puts out to please read up on it. I keep my cells in a safe place away from the kids, and the lights with lith rechargeables in it are safely put up til needed. Treat the cells with care and always use a dmm to check the voltage before you put the cells on the charger and to check after it has charged, doing this all the time will become second nature.

Wow. People warn everyone like crazy about li-ion batteries, but I'm surprised how few bad incidents like this actually happen. I wonder if there was a short or he had a battery reversed? I had a spring on the back of the driver come loose one time and it shorted the battery + and - which would have caused a fire pretty quickly I think if I had been using the flashlight, but fortunately I was measuring current and realized something was wrong (it was my fault the spring came loose; I'm a lot more careful now). Now when I have a light that doesn't come on when I press the button, I don't fiddle around with the switch (except maybe to turn it off), I take the tailcap off immediately and see what's wrong.

I have seen lipo packs used at the rc tracks, all you see is your ride on fire going into the straight. Not funny at all for the owner but it was a sight to see though. And havent you noticed that they were mostly talking about one brand, for me it could happen to any cells that the user had around be it AW's etc.

Four days ago I received a pack of 14500 and a pack of 16340 protected flame batteries from DX after reading good about them on this site. The two 14500 and one of the 16340 charged OK to 4.17 V but the last 16340 had a voltage of zero and made my charger (Cytac, the same as TR001) go bananas with flickerings leds. I then put the battery on a power supply at 100 mA and could watch the voltage slowly rising to over 3 Volt. The Cytac was now happy with it and charged it to the normal 4,17V.

Now, after resting 4 days, the 14500 are 4.15V, the "good" 16340 is only 4.08V and the "bad" 16340 is 4,02V.

I now wonder which hazard I'm going into by using those two 16340 in my coming 16340 flashlight.

Caution! throw that 16340 to the garbage! (the one received at 0 volts) and ask for replacement. That battery can become in "unstable condition" and explode, fire your house, etc.......

I would toss it without feeling bad at all.

Save the cell but mark it so that you can keep track of it. Also, do not use cells of different state (charge, wear, age, manufacture etc) together in a series configuration.