Jump to content

Lithium battery - Fire hazards in our cars


 Share

Recommended Posts

Just sharing some of my thoughts and knowledge gathered from reading several articles on the topic. You are welcome to comment. My intention is to raise the awareness of people who are unknowingly taking on excessive risks.

 

Many of you will be aware of the fire hazards of Lithium batteries. We have learnt to accept these hazards knowingly or unknowingly. The technology had been improved and the risks decreased over the years. The risk is never zero.

 

Well known cases include Sony laptop batteries and the recent Boeing battery problems. There are many more. Even reputable MNCs like them face problems given their strict Quality/Reliability/Safety requirements and qualifications. Some of us use Lithium secondary cells without safety certification like UL1642 to power DVRs in our cars 24/7, under the hot sun and unattended. I hope to raise your awareness to the risks of Lithium battery thermal runaways and internal short circuits failure modes. I am not sure typical comprehensive auto insurance in Singapore covers such non-OEM "modifications". I need comments on this.

 

There are simple mitigations that the ordinary consumer can adopt to reduce the risks. It may be troublesome but it takes care of the most risky phases of Lithium battery usage to avoid catastrophic outcomes. I list some of my personal ones, which include non-car related.

 

- Never charge phones beside you when sleeping. I mandate this on my family recently.

- Avoid having Lithium battery less than ~40% of charge whether in usage or storage. Undercharge conditions increase risks of internal short circuit that can start a fire, even under storage.

- Overcharge is also dangerous, but this is usually not a problem as batteries and charger nowadays have automatic cutoff.

- Avoid high temperatures. In Singapore, car parked under the hot sun has induced internal temperature of 60 to 70 degress C. This greatly increase risks of a thermal runaway condition internal of the battery and start a fire. I know people have done tests to show DVRs work under such conditions. I do not think these tests are done over the long term and with enough sample size. You need just 1 event over the lifetime of a battery to create a catastrophic outcome.

 

↡ Advertisement
Link to post
Share on other sites

Good to know. I always charge my phone on my bedside table. Do you have any of the links or maybe keywords that you used to google up such articles? Thanks

 

Link to post
Share on other sites

TS may have a point on the suitability on the use of lithium batteries inside cars.

 

My BV DR400G Season II kaput first time, I ripped out the bloated 3.7V lithium-polymer (li-po) battery & replaced it with a similar 3.7V li-po battery with a slightly higher current rating.

 

Unfortunately the replacement also kaput soon after with the same bloated situation.

 

So now I still operate the BV but without any li-po battery at all & it still works since the BV is rigged directly to my car battery for 24/7 operation so no issues with the date & time settings. (FYI I also took out the internal button battery & permanently damaged the terminals by accident [laugh] [laugh] )

 

But this is just my personal experience so need our guru Adrianli to comment since he has 1,001 DVRs inside his ride and also use a portable one which he charges daily.

Link to post
Share on other sites

TS may have a point on the suitability on the use of lithium batteries inside cars.

 

My BV DR400G Season II kaput first time, I ripped out the bloated 3.7V lithium-polymer (li-po) battery & replaced it with a similar 3.7V li-po battery with a slightly higher current rating.

 

Unfortunately the replacement also kaput soon after with the same bloated situation.

 

So now I still operate the BV but without any li-po battery at all & it still works since the BV is rigged directly to my car battery for 24/7 operation so no issues with the date & time settings. (FYI I also took out the internal button battery & permanently damaged the terminals by accident [laugh] [laugh] )

 

But this is just my personal experience so need our guru Adrianli to comment since he has 1,001 DVRs inside his ride and also use a portable one which he charges daily.

 

The bloating is due to gas venting internally of the cell when a short occurs.

In some more severe cases, huge amount of gas vents and creates very high temperature. Thereafter, the battery catches fire. The fire may spread if there are other materials around it to burn.

 

 

Link to post
Share on other sites

Good to know. I always charge my phone on my bedside table. Do you have any of the links or maybe keywords that you used to google up such articles? Thanks

 

I am not a battery expert. My job involves safety and Lithium battery safety is one of the topic.

Some websites that I read up from.

 

http://www.mpoweruk.com/lithium_failures.htm

 

http://batteryuniversity.com/learn/article...rns_with_li_ion

 

You can go to Youtube and search under "Lipo fire". You will get alot of videos showing people intentionally causing Lipo and Li-ion batteries to fail by puncturing them. In some safety standards for batteries, they do use nail penetration tests to simulate an internal short. So such drastic testing is not uncorrelated from real life.

An example:

 

Link to post
Share on other sites

bro, our car still using acid lead battery, where got lithium ?

you mean video recorder inside the car ?

Link to post
Share on other sites

Guys, do not be too alarm in using Lithium batteries. Today they are much more safer and still improving. My purpose here is just to highlight the real hazards so that you know what are the mitigations you can adopt to avoid catastrophic outcomes.

 

I myself have 2 DVRs in my car with built-in Lithium batteries. I only need them on while driving. My car is parked outdoors in my workplace. Nowadays, i park under a tree for shade even though i get more leaves and bird poo. Risk is not eliminated but probability is reduced. Next, i will try to see if I can remove the batteries, since i have no use for them to operate while parked.

Link to post
Share on other sites

bro, our car still using acid lead battery, where got lithium ?

you mean video recorder inside the car ?

 

Yes, our cars are using Lead acid battery. Most hybrid cars like Civic is using Nickel Metal Hydride which are relatively safe.

 

I am refering to Lithium rechargeable batteries in car DVRs, smart phones/tablets left inside cars, etc.

Link to post
Share on other sites

Bear Grylls managed to start a fire using just a lithium battery from a damaged Nokia phone.

 

All he did was splice open the batt with his knife and there was a lot of sizzles.. put some dry twigs over and you got fire.

Link to post
Share on other sites

Yes, our cars are using Lead acid battery. Most hybrid cars like Civic is using Nickel Metal Hydride which are relatively safe.

 

I am refering to Lithium rechargeable batteries in car DVRs, smart phones/tablets left inside cars, etc.

 

gps using such batt will catch fire easily?

Link to post
Share on other sites

gps using such batt will catch fire easily?

 

 

I wouldn't say they catch fire "easily". That sounds like it happen everyday, which is not.

 

Yes, my comments in this thread refer to Lithium rechargeable battries used in GPS or any electronic devices. The 2 most common types are Lithium polymer and Lithium ion. There many types of less common Lithium based batteries. Some of them are relatively safer like Lithium iron phosphate, as the runaway temperature is much higher.

Link to post
Share on other sites

The bloating is due to gas venting internally of the cell when a short occurs.

In some more severe cases, huge amount of gas vents and creates very high temperature. Thereafter, the battery catches fire. The fire may spread if there are other materials around it to burn.

 

Bro what causes the short then?

 

Inferior batt quality or some other causes?

 

Curious to know.

Link to post
Share on other sites

Yes, our cars are using Lead acid battery. Most hybrid cars like Civic is using Nickel Metal Hydride which are relatively safe.

 

I am refering to Lithium rechargeable batteries in car DVRs, smart phones/tablets left inside cars, etc.

 

The current Honda Civic Hybrid is using Lithium Ion battery which is 35% smaller than previous Nickel Metal Hydride. Any risk?

Link to post
Share on other sites

Bro what causes the short then?

 

Inferior batt quality or some other causes?

 

Curious to know.

 

What was the exact root cause for your case? Even if detailed failure analysis was done on the swollen battery, the answer may never be found. Even Boeing, the NTSB and GS-Yuasa do not know the root cause of their Li-ion battery fire after 3 months of investigation.

 

I can only share my knowledge from a general point of view.

Some typical root causes that have been thrown up in past cases:

 

- Manufacturing quality defects where tiny metallic particles were trapped in the cells. These later caused the shorts.

 

- High temperature. Li-ion cells can exhibit internal swelling at 60degC or higher due to gas released from the chemical reaction between the electrolyte and the active carbon material on the electrodes. In chemistry this is know as the Arrhenius behaviour where chemical reactions increase with temperature. If there is no thermal runaway (where the temperature just keeps increasing) then it is just swelling and stop at that. I think this is what happens in your case. I am not advertising dvr brands here, but I am aware that blackview dvr users complain of heat problems. Different brands of Li-ion batteries use different materials inside. And theses different materials have different characteristics (flash point, etc). They are meant for different types of applications like low or high temperatures. I have read an article or blogpost somewhere where someone modded his blackview dvr as some of the IC components were not ventilated properly, causing internal heat issues within the case. That person made some openings and added heatsinks to some of the hot ICs and lowered the operating ambient heat of the dvr. So, poor thermal design of the device that the battery is used in is a factor as well.

Link to post
Share on other sites

(edited)

if lithium is bad, what about the old nickel cadmium?

 

Lithium batteries are not bad. They are new technology and make possible that small smartphone that fits in your hand. The energy density and current rate are much better than the older technology like NiCd and NiMh. This is why many products are using them , especially those that are weight and space challenged.

 

Nickel cadmium batteries are relatively safe, tried and tested and matured.

After the Boeing Li-ion battery case, Airbus announced that they will revert back to the safer NiCd batteries for their A350 instead of Lithium batteries.

Edited by Columbian78
Link to post
Share on other sites

The current Honda Civic Hybrid is using Lithium Ion battery which is 35% smaller than previous Nickel Metal Hydride. Any risk?

 

I cannot comment on the risks of Honda's Li-ion battery cos I do not know much of it.

Such battery are more complex comprising of multi-cells with more protection in the design than the usual single cell used in a small device like car dvr. They need to be well certified by automotive standards and passed stringent testings. But so was the Boeing battery...

 

I would just say, if you need to get a Lithium battery, get one from a reputable source with safety certifications (e.g. UL1642). At least this will greatly reduce the risk. And don't be an early adopter if you cannot take risks.

 

 

↡ Advertisement
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...