How do you think of charge to 4V or 80% capacity?

XTAR Light

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Some users told charging a Li-ion battery to 4V or 80% capacity, let it last longer when not using for a long time. And the 80% charging energy also makes it suitable for normal use. It seems this option achieves the balance between battery longevity & usability. Some people prefer the batteries to be fully charged 4.2V before using them in devices. For storing them when not using, charge them at 3.7V.

How about your opinion on these charging options? Comment below.
 

desert.snake

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It seems that charging up to 80% is used in electric vehicles to increase durability. @jon_slider once gave me extremely helpful articles about it :




It would be cool if there was a flashlight with built-in batteries and a built-in charger that would charge it up to 4V and switch to super-saving mode at 3.7V (run 1 level, max 5-8 lm). It would make a very reliable flashlight, but manufacturers of batteries and flashlights are hardly interested in this. If there is an almost eternal device, then who will buy a new one, and where will the money come from to develop better batteries and flashlights?

It is necessary to make sure that the battery dies after 300 cycles or after 1.5 years of use (and the LED after 3 years). And it is necessary to agree on this between all manufacturers, as was once done between manufacturers of incandescent lamps.

For example, something oval, similar in appearance to Lupine Piko TL, but with a usb-c built-in charger for built-in 2 * 21700, reflector + TIR (a mule-COB 25-30 degress and something like XHP50.3 HI 7-12 degress for medium range), 2 buttons for separate control of emitters.
 
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alpg88

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charging to 80% is not enough to prolong your battery life significantly, you need to discharge it no lower than 40%, so basically you use half of the battery capacity. maybe ok for electric cars that have 20k batteries, but for a flashlight, it is not worth at all, imo.
 

KITROBASKIN

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Totally worth it to be able to easily give a storage charge to flashlight batteries. I make an effort to charge a cell phone up to 80% but not a big deal if it charges higher. Our primary charger at home (XTAR VP2) is easy enough to pull batteries once they exceed 4V.

More and more people are turning away from the throw-away culture of the past.
 

cave dave

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I would like it! I manually charge to 3.8v (for storage) and between 4.0v - 4.1v (for casual use) pretty often, but I have to set a timer and pay attention. It would be easier to set and forget till it's done. I would like to be able to discharge to 3.8v as well.
 

alpg88

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hobby chargers can do that, they have storage charge mode, and they can discharge it to any voltage you set. my hitek x4 does it, even some universal chargers with slots like xtar vc4-8, have storage function, however you can not control discharge voltage.
 

desert.snake

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hobby chargers can do that, they have storage charge mode, and they can discharge it to any voltage you set. my hitek x4 does it, even some universal chargers with slots like xtar vc4-8, have storage function, however you can not control discharge voltage.
SkyRC does it (in manual mode, can set any final charging voltage), but it's too expensive))

Tests have shown that the life time (number of cycles) at 80% charge increases well
1679726556611.png

It would certainly be even better if the flashlight itself did not discharge the batteries too low and also did not draw too much current from them. For example, some 1-2 element flashlight, which in the first 10 seconds will give out 5000 lm and then decrease to 1000 lm, then the operating time of 80% of the charged batteries will be really short and the battery can age faster due to high current and overheating. But if the flashlight consumes 0.5-1C from the battery during the main part of the time of use, then this will be a very longlife tandem :)

I would also buy this charger. I have Xtar X2, excellent charging, but I would like to know how to turn off the charging of long batteries on 2A / 1A and turn it into 0.5A, or find a current selection switch. In general, due to the fact that I have several old ICR batteries and I suspect that 2 or 1 amps is a bit fast for them
 

bykfixer

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Coming from a "throw away" culture, the way I see it is those were used once. Only once. If charging to 80% gets me 1000 cycles and 100% gets me 500 cycles.... either one is fine by me. If charging it to 100% gets me 20% more runtime I'll take the reduced number of potential recharges. I may need that 20% due to no option of replacing said battery at a time when I need light.

Post apocolypse in my first world life style where batteries are hard to come by, yeah I'd want as many cycles as possible.
 

Sjvalleydave

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I would like it! I manually charge to 3.8v (for storage) and between 4.0v - 4.1v (for casual use) pretty often, but I have to set a timer and pay attention. It would be easier to set and forget till it's done. I would like to be able to discharge to 3.8v as well.
I use a UP100ac+ and you can adjust the level of amps charging or draining and set the cutoff min. If you tell it to charge to store, it will be 3.65v and turnoff.
 
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