Lithium Battery fires ..........

[Murdoch]

Anyone read this?

https://www.electricalsafetyfirst.o...90f0737ca22e8&utm_source=ESF Campaign Monitor

 

[MikeJhn]

I would ask, what makes these people the "The UK Electrical Safety Experts."

The are late to the party, the BMFA (British Model Flying Association) has had recommendations for the safe charging of LiPo and LiIon batteries for over twenty years to my recollection, and most fires have been caused by incorrect charging (wrong charger settings) or charging a damaged battery, this can be caused by over discharge or physical damage. We all know that when our LiIon drill stope we can usually get another screw of use out of the drill for a few seconds, this can cause one of the cells to break down or even reverse charge with irreparable damage.

 

[binky]

The government should legislate that all batteries should be LiPO4 which does not self propagate fires in the cells

 

[johnb2713]

The government should legislate that all batteries should be LiPO4 which does not self propagate fires in the cells

LiFEP04 surely, LiPO's are relatively unstable?

 

[binky]

LiFEP04 surely, LiPO's are relatively unstable?

Couldn't think exactly how to spell it, but yes, that battery chemistry.

 

[johnb2713]

Couldn't think exactly how to spell it, but yes, that battery chemistry.

I know what you mean, in my case I put it down to old age and dont fight it. Do you know the three stages of a mans love life?

Tri Weekly
Try Weekly
Try Weakly

I'm at stage 3

 

[apprentice87]

Seen this?? https://www.gov.uk/government/publications/recovery-operators-working-with-electric-vehicles

Would not want one of the things..

john..

 

[johnb2713]

Seen this?? https://www.gov.uk/government/publications/recovery-operators-working-with-electric-vehicles

You are more likely to see a fire with a petrol or diesel vehicle than an electric one. Petrol tanks are wonderful things when fire fighting and a nice trail of fuel from a ruptured fuel tank spreads the blaze nicely. An electric vehicle is far less likely to catch fire, if it does the flames are there but going nowhere else, the fire crews simply cool it down to take the heat away from it. It presents a lot less danger to the environment and to the public in general.

Would not want one of the things..

john..

Each to their own, sadly the pollution caused by you and many others is killing everyone! I wouldnt go back to an ICE vehicle, ever.

 

[MikeJhn]

The government should legislate that all batteries should be LiPO4 which does not self propagate fires in the cells

Not correct I'm afraid, In a fire it's the lithium in the battery that give's off Oxygen as it burns and therefore self supplies the fire.

 

[binky]

Not correct I'm afraid, In a fire it's the lithium in the battery that give's off Oxygen as it burns and therefore self supplies the fire.

Yes, but some self propagate oxygen when overheated, others don't do this. So standard LiIon will generate oxygen as it breaks down, causing thermal runaway in the neighbouring cells as a failed cell burns, and hence the nasty fires we have been seeing. If you use battery chemistry that doesn't release oxygen, then a single failed cell is far less likely to cause it's neighburs to overheat and burn in a runaway fire. Tesla did some interesting testing in regards to this.

https://electrek.co/2016/12/19/tesla-fire-powerpack-test-safety/

 

[MikeJhn]

That's just one manufacturer who have cleverly contained the thermal runaway, however, you can't change the chemistry of Lithium, it will release Oxygen on thermal runaway.

 

[binky]

That's just one manufacturer who have cleverly contained the thermal runaway, however, you can't change the chemistry of Lithium, it will release Oxygen on thermal runaway.

They are not alone. That wasn't the video I was particularly looking for, but interesting non the less. I was trying to find videos of single cell self propagating a fire because it releases oxygen v one that doesn't - it's been a concern with PV batteries for a while. I also suspect half the issue is cheap charger designs and battery construction. I've not heard of a solar battery going boom yet, whatever the chemistry, but solar inverters do have a lot of battery management systems built in to monitor and control the cells.

 

[MikeJhn]

Unlike lead acid batteries, any multi cell Lithium based battery needs each individual cell monitored to ensure balanced charging, in a decent charger the pack will also be temperature monitored to try and prevent thermal run away, but my response to your original post concerning Li batteries still stands, No lithium battery is immune from thermal run away, lithium gives off Oxygen when it burns and therefore self propagates a fire once started.

The government should legislate that all batteries should be LiPO4 which does not self propagate fires in the cells

 

[MikeJhn]

For information LiPO4 designation originated in China when they ripped off the original Lithium Nano Phosphate battery from the American A123 company some 20, maybe 30 years ago. LiPo originally stood for Lithium Polymer which tended to have a soft case and where easily damaged, the LiIon batteries where hard cased, but still the same chemistry internally, it was interesting that the original A123 cells where 3.6v @3300mah, but the LiPO4 where 3.3v and had a different capacity, can't remember, but it was lower.

 

[johnb2713]

For information LiPO4 designation originated in China when they ripped off the original Lithium Nano Phosphate battery from the American A123 company some 20, maybe 30 years ago. LiPo originally stood for Lithium Polymer which tended to have a soft case and where easily damaged, the LiIon batteries where hard cased, but still the same chemistry internally, it was interesting that the original A123 cells where 3.6v @3300mah, but the LiPO4 where 3.3v and had a different capacity, can't remember, but it was lower.

LiFePO4 batteries which are the battery of choice these days are much better in terms of fire, they need a lot of provoking for them to burn and when they do it's not as ferocious as LIPO. The terminal voltage is higher too at 3.7v

 

[binky]

LiFePO4 batteries which are the battery of choice these days are much better in terms of fire, they need a lot of provoking for them to burn and when they do it's not as ferocious as LIPO. The terminal voltage is higher too at 3.7v

You have to love 'hill billy' testing methods

 

[johnb2713]

You have to love 'hill billy' testing methods

Absolutely but it was pretty impressive just how much abuse it got just to make a small fire.

 

[johnb2713]

Unlike lead acid batteries, any multi cell Lithium based battery needs each individual cell monitored to ensure balanced charging, in a decent charger the pack will also be temperature monitored to try and prevent thermal run away, but my response to your original post concerning Li batteries still stands, No lithium battery is immune from thermal run away, lithium gives off Oxygen when it burns and therefore self propagates a fire once started.

Things have moved on

Here are the test results for extreme conditions with EVE cells (LifeP04).



In every extreme test - NO FIRE, NO EXPLOSION!


Locked to prevent hi-jacking (again)