The inadvisability of charging LiFePO4 batteries below 32F/0C (akabelow freezing)

On Tuesday, March 20, 2018 at 9:51:23 PM UTC-7, 2G wrote:
On Sunday, March 18, 2018 at 8:29:30 AM UTC-7, Dan Marotta wrote:
Well, what immediately comes to mind is the confusion between LiFePO4 and Lithium Ion. Those are different chemistries. I used LiFePO4 and charged them over the winter months in NM (lots of zub-freezing nights) using the chargers supplied with the batteries without any problems. After a year of removing the batteries and taking them home to charge, I had the confidence to leave them installed in the glider, in the hangar, with the chargers connected and plugged in. Again, no problems with LiFePO4. YMMV.

Dan

On Sunday, March 18, 2018 at 8:38:12 AM UTC-6, son_of_flubber wrote:
When researching a step up to LiFePO4, I stumbled across this tidbit at http://batteryuniversity.com/learn/a...w_temperatures

"Many battery users are unaware that consumer-grade lithium-ion batteries cannot be charged below 0°C (32°F). Although the pack appears to be charging normally, plating of metallic lithium can occur on the anode during a sub-freezing charge. This is permanent and cannot be removed with cycling. Batteries with lithium plating are more vulnerable to failure if exposed to vibration or other stressful conditions. Advanced chargers (Cadex) prevent charging Li-ion below freezing."

Advancements are being made to charge Li-ion below freezing temperatures. Charging is indeed possible with most lithium-ion cells but only at very low currents. According to research papers, the allowable charge rate at –30°C (–22°F) is 0.02C. At this low current, the charge time would stretch to over 50 hours, a time that is deemed impractical. There are, however, specialty Li-ions that can charge down to –10°C (14°F) at a reduced rate."

The also applies to lithium battery in your phone/computer. If you should happen to leave it in a cold place, you might want to warm it up before charging.

There's no confusion between LiFePO4 and Lithium Ion because LiFePO4 IS a Lithium Ion battery. Lithium Ion is a generic term that includes all lithium chemistries.
http://batteryuniversity.com/learn/a...of_lithium_ion

There should not be, but unfortunately there is confusion, because of the loose use of the terminology. If it has lithium in it, it is a Lithium Ion battery, but beyond that there are big differences in chemistry and mechanical construction. The concern about sub zero charging has to do with plating on the anode, however each of these different battery chemistries use a different anode material. One might assume that with different anode material they would be more, or less, susceptible to the plating problem. I cannot find any scholarly paper that discusses LiFePo4 in particular, with respect to charging temps.

On Wednesday, March 21, 2018 at 1:10:56 AM UTC-4, jfitch wrote:

If it has lithium in it, it is a Lithium Ion battery...

Given the different charging/discharging *requirements* associated with "LiIon" vs "LiPo" vs "LFP", that's a very dangerous statement.

T8

On Wednesday, March 21, 2018 at 7:30:38 AM UTC-7, Tango Eight wrote:
On Wednesday, March 21, 2018 at 1:10:56 AM UTC-4, jfitch wrote:

If it has lithium in it, it is a Lithium Ion battery...

Given the different charging/discharging *requirements* associated with "LiIon" vs "LiPo" vs "LFP", that's a very dangerous statement.

T8

The truth is never dangerous, but ignorance is. What people need to do is get used to saying LiPo or LiCo, or LiMn or LiFePo4 (LFP for short). The danger is in ignorance that these are different batteries. You don't charge NiCads the same as SLA the same as flooded LA do you? Yet they are all batteries. The details matter. Even in your post you imply that LiIon is different than LFP. An LFP is a LiIon (it uses a lithium compounded anode or cathode, and ions to transport current). There is a wide variety of lithium based batteries just as there is a wide variety of carbon, nickel, and lead batteries. Treat them the same at your own peril - please educate yourself.

.... And so is "gas".Â* Try putting jet fuel in your piston engine and see
what happens.Â* Or diesel in your car or vice versa.Â* I used to gas up
the jet and the King Air after a mission or flight, but I never used
avgas or mogas in any of them.

The Boeing 787 didn't use LiFePO4 batteries, either, if I"m not
mistaken.Â* Their "generic" lithium ion batteries had a tendency to burn
during ground charging.Â* Generic terms can get one killed in certain
circumstances.

On 3/20/2018 10:51 PM, 2G wrote:
On Sunday, March 18, 2018 at 8:29:30 AM UTC-7, Dan Marotta wrote:
Well, what immediately comes to mind is the confusion between LiFePO4 and Lithium Ion. Those are different chemistries. I used LiFePO4 and charged them over the winter months in NM (lots of zub-freezing nights) using the chargers supplied with the batteries without any problems. After a year of removing the batteries and taking them home to charge, I had the confidence to leave them installed in the glider, in the hangar, with the chargers connected and plugged in. Again, no problems with LiFePO4. YMMV.

Dan

On Sunday, March 18, 2018 at 8:38:12 AM UTC-6, son_of_flubber wrote:
When researching a step up to LiFePO4, I stumbled across this tidbit at http://batteryuniversity.com/learn/a...w_temperatures

"Many battery users are unaware that consumer-grade lithium-ion batteries cannot be charged below 0°C (32°F). Although the pack appears to be charging normally, plating of metallic lithium can occur on the anode during a sub-freezing charge. This is permanent and cannot be removed with cycling. Batteries with lithium plating are more vulnerable to failure if exposed to vibration or other stressful conditions. Advanced chargers (Cadex) prevent charging Li-ion below freezing."

Advancements are being made to charge Li-ion below freezing temperatures. Charging is indeed possible with most lithium-ion cells but only at very low currents. According to research papers, the allowable charge rate at –30°C (–22°F) is 0.02C. At this low current, the charge time would stretch to over 50 hours, a time that is deemed impractical. There are, however, specialty Li-ions that can charge down to –10°C (14°F) at a reduced rate."

The also applies to lithium battery in your phone/computer. If you should happen to leave it in a cold place, you might want to warm it up before charging.
There's no confusion between LiFePO4 and Lithium Ion because LiFePO4 IS a Lithium Ion battery. Lithium Ion is a generic term that includes all lithium chemistries.
http://batteryuniversity.com/learn/a...of_lithium_ion

--
Dan, 5J

I would argue that.
If you stated "fuel", then your argument carries more weight.
I think most peeps, when they hear "gas" assume (yes, I know what that may also mean...) you mean gasoline/petrol.
When you say "fuel", yes, there can be a mix up.
Heck, coal is a fuel, don't think anyone is shoveling coal into an aircraft.....LOL.......

Yes, LiFe is a lot different than LiPo or LiOn.
LiFe is a lot closer in safety to LA than other Lithium chemistries.

On 03/21/2018 08:29 AM, Charlie M. (UH & 002 owner/pilot) wrote:
I would argue that.
If you stated "fuel", then your argument carries more weight.
I think most peeps, when they hear "gas" assume (yes, I know what that may also mean...) you mean gasoline/petrol.
When you say "fuel", yes, there can be a mix up.
Heck, coal is a fuel, don't think anyone is shoveling coal into an aircraft.....LOL.......

Yes, LiFe is a lot different than LiPo or LiOn.
LiFe is a lot closer in safety to LA than other Lithium chemistries.


What's so funny about shoveling coal into an aircraft?

http://www.thevintagenews.com/2016/1...ueled-by-coal/