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Old March 22nd 18, 12:00 AM posted to rec.aviation.soaring
Andrzej Kobus
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Posts: 585
Default The inadvisability of charging LiFePO4 batteries below 32F/0C(aka below freezing)

On Wednesday, March 21, 2018 at 7:18:52 PM UTC-4, jfitch wrote:
On Wednesday, March 21, 2018 at 12:12:31 PM UTC-7, Tango Eight wrote:
On Wednesday, March 21, 2018 at 2:15:26 PM UTC-4, jfitch wrote:
On Wednesday, March 21, 2018 at 10:22:48 AM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
While I usually don't disagree with you, if you READ what Tango8 posted, he is saying the same thing as you.
"Lithium in the name does make it the same", as I read it.

Your thoughts?!

Yes, I am going from early (late '70's NiCads to more modern LiFe or LiOn/LiPo) rechargeables including LA of various flavors.

I have a bunch of cash tied up in chargers for various battery chemistries, mostly in RC use, but also for my main income.

Hey, hey find an issue with my read of Tango8's post, I am willing to learn, but I believe you read it wrong.

I don't believe it is dangerous to refer to Lithium Ion batteries as Lithium Ion batteries. But in T8s post he said it was, and further said '"LiIon" vs "LiPo" vs "LFP"' which implies that Lithium Ion batteries are a type of Lithium Ion batteries. The semantics matter. Had he quoted my post in context (the complete sentence was "If it has lithium in it, it is a Lithium Ion battery, but beyond that there are big differences in chemistry and mechanical construction.") perhaps he would have not thought what I said dangerous. You cannot charge a LiIon battery differently than an LFP, because an LFP IS a LiIon battery. LiIon includes all the different chemistries but the members of that group differ in their associated charge requirements.

It is much better to use language precisely when the result of a misunderstanding can be an explosion and fire. If you specify an LFP charger you should get want you want. If you specify a LiIon charger you have no idea what you are going to get.


Jon, you're clearly unfamiliar with the terminology as it is used out in the real world. There are many (millions) multi-mode chargers out there that use the terms as I have used them, "LiIon, LiPo, LFP". Semantics matter? Sure. Safety based on correctly matching charging cycles to chemistry matters more.

Here's a link to the instructions for a commercial charger that illustrates what I am talking about. They use the terms LiIo, and LiFe instead of LiIon and LFP.

http://www.ircha.org/sites/default/f...tam%20BC6..pdf


I am well aware of the loose and incorrect usage of terms, and it is what I am arguing against as potentially dangerous. As I said in my second post in this thread, "unfortunately there is confusion". What exactly is the voltage and chemistry of a LiIo, or LiIon, or Lithium battery? In the real world, Google "lithium ion battery" will correctly return hits on all types, not just lithium polymer, with recommended charging voltage of between 3.2 and several hundred volts. Even in the last few of posts we have the conflation of several chemistries. The news media is horribly guilty of this, from them we know that lithium batteries cause cars and aircraft to catch fire and burn, and hoverboards to self immolate. I have been told on this very forum that lithium ion batteries should not be used in gliders because they cause Boeing 787s and Chevy Volts and Samsung S7s to burn - never mind that those batteries are quite different than the ones we use.

If I have a charger than says "LiIo" or "lithium" charger on it, that tells me little or nothing about what battery I can charge with it. This is my point. "Correctly matching charing cycles to chemistry" can only be done if the specific chemistry or voltages required are stated. "Lithium ion" is the term used for the collection of chemistries using lithium anodes or cathodes. If that is not the correct term, then what is? And why is it "dangerous" to use the correct term? And if speaking in a context where the specific chemistry dangerously matters, shouldn't the specific term be used, rather than the general?


John, I am sorry, but aren't you the one who uses unapproved, for starting, LiFePo4 batteries in your ASH-26E for engine starting? I am surprised you seem to lecture others while you do questionable things yourself, just saying.