Very basic questions
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A maintainer won't significantly warm a battery when it is in float mode. Lithium batteries should not be charged below freezing...
"When your batteries internal temperature drops below 32 degrees, the lithium cells are unable to accept the same amount of charging current (warmth) as they did when the temperature was warm. Don’t charge your lithium batteries when the battery temperature is below freezing."
Are Lithium Batteries Good in Cold Weather?
Not sure what happens to your lithium batteries when it's cold? If yes, this is a must-read. Find out why you can use your battery no matter how cold it gets!
lithiumhub.com
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So I’m asking again….an alternator will charge a lithium battery how in cold weather? Your statement above states “internal temperature”. So the key is keeping the internal temp above 25F. A slight current draw or charge will generate some heat.I’m Simply advising Robh that a maintainer should help, but I may have missed where he’s located. Extreme cold would be a good reason to remove the battery or move the whole generator to a warmer location. You certainly don’t want to struggle with equipment in the middle of an emergency…😬
Any Lithium-battery BMS (battery management system) worth its salt is going to halt charging as the cell temp approaches freezing. A phenomenon called Lithium plating will result if it doesn't.
Once a Lithium cell reaches 32F (actually, even before it gets that cold) external heat must be applied to first raise its temperature.
Lithium batteries are mostly used in consumer devices, of course, which are typically kept indoors at moderate temps, so it's not an issue. For things like electric vehicles, if it becomes very cold things like charge rates and regenerative braking are reduced until the pack temp can be raised. In a Tesla that happens by the BMS sending power to the stator(s) of the drive units and using the waste heat thus created to warm the pack coolant, which then circulates and heats the cells.
IMO, Lithium-chemistries are a very poor choice as starter batteries for equipment like generators that typically are kept in sheds, barns, garages, etc. where temperatures may approach freezing. The float circuit in a battery maintainer doesn't generate enough current to make an appreciable difference.
Once a Lithium cell reaches 32F (actually, even before it gets that cold) external heat must be applied to first raise its temperature.
Lithium batteries are mostly used in consumer devices, of course, which are typically kept indoors at moderate temps, so it's not an issue. For things like electric vehicles, if it becomes very cold things like charge rates and regenerative braking are reduced until the pack temp can be raised. In a Tesla that happens by the BMS sending power to the stator(s) of the drive units and using the waste heat thus created to warm the pack coolant, which then circulates and heats the cells.
IMO, Lithium-chemistries are a very poor choice as starter batteries for equipment like generators that typically are kept in sheds, barns, garages, etc. where temperatures may approach freezing. The float circuit in a battery maintainer doesn't generate enough current to make an appreciable difference.
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Speaking of cars, did you notice on the news that many people had charging issues with their electric cars during that bitter cold snap a few weeks ago. It was a surprise that they didn't expect for sure!
Yeah, that was quite something in the EV community when that bomb cyclone rolled across the continent! There was an awful lot of misunderstanding and more than a little consternation. But at least EV's typically have far more sophisticated BMS's than do most Lithium-powered devices... that mostly hides all the ugly details from users.
I've got a Tesla Model 3 but unlike most EV owners I live out in the country, and the Tesla is parked outside a shed, a hundred feet from the house. When that storm rolled through I bumped my charge-to state of charge 10%, and remotely triggered battery pre-heating (via the app on my phone) a good 45 minutes before going for a drive.
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To help explain Dutchy, I pulled this from the same Wen manual. Basically what's been stated above.
All this has helped explain to me the reasoning of why my cordless tools act up when I first grab them in a cold shop. Same goes for charging, they've never liked (been very slow to react) when being put on a charger until I've warmed the shop.
I already knew the cold affected them, I just didnt know the why.
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WEN states there that "Lithium-ion batteries can be damaged or suffer a shortened lifespan if they are charged in very cold temperature (below freezing)."
Freezing is 32°F (0°C), so the reference to 25°F (-5°C) does not make sense.
I agree that the battery should be stored indoors if freezing conditions can occur in your area. In below freezing weather the battery could be taken to the gen to get it up and running, removed, and then reinstalled after the gen has warmed up inside. Of course, this would only apply to enclosed inverter gens because open frame units will not heat up "inside".
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Yeah, I noticed that. I get what they are basically stating, 'Be aware when temps approach the freezing mark'
They do mention removing or dis-connect for a short span until warmed. Adding the quick dis-connect would help lessen the fumbling around.
They do mention removing or dis-connect for a short span until warmed. Adding the quick dis-connect would help lessen the fumbling around.
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use a battery blanket heater.
we do this on the equipment in the fleet.
most batterys will hold temp till you get it started if it had been plugged in till the power went out.
and we use magnetic heaters on the engine blocks under mounting that is steel.
like on the eu7000i gens.
nice to have warm oil before a start up.
and if the battery is warm they start up quick.
an insulated temp controlled gen shack helps for sure.
we do this on the equipment in the fleet.
most batterys will hold temp till you get it started if it had been plugged in till the power went out.
and we use magnetic heaters on the engine blocks under mounting that is steel.
like on the eu7000i gens.
nice to have warm oil before a start up.
and if the battery is warm they start up quick.
an insulated temp controlled gen shack helps for sure.
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