Charging Question

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singularity35
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Charging Question

Hey guys, I hope this is the right forum for this question, if not mods please move.

Anyway, I have a few ultrafires for my lights and I recently got a nitecore i4. Would it be safer to not wait for the batts to get fully charged or would it be ok to always get them fully charged? Thanks in advance.

yuhsin91123
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I was going ask the VERY SIMILAR question… I like to have my battery fully charged all the time, therefore: I will be charging the battery after like 3 mins of use…. is this bad for the battery or not

And to OP, Ultrafires battery….. No offense but I would suggest you other batteries if you have a high performance flashlight.

Franz
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Ultrafire batteries are not safe anyway

So, for lithium batteries 100% of charge and under 20% is not health but for our use chaging under 100% are not practical…..

I wouldnt charge a battery with too much use Big Smile

singularity35
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Haha thanks, point taken. I never looked at good batts before since I was using only the cheap generic chargers from ebay.

Barkuti
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BU-808: How to Prolong Lithium-based Batteries @ Battery University

 

In essence: above 14/15th of maximum battery voltage and you start hammering nails in the coffin of your battery, the higher/the faster. Smile

With regards to potential battery damage caused by low state of charge, I believe most information is a busted myth. Briefly after battery management cut-off most cells will end up lieing well above 3V, at these levels damage, if present, is for sure minimal, at least compared to high voltage stresses.

 

Cheers Party

P.S.: most flashlights do not have cell cut-off mechanisms, just low battery warnings. It is, thus, your duty to remove cells from them or do tailcap lock-outs if parasitic drain is present (or just do it).

Zulumoose
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Barkuti wrote:

In essence: above 14/15th of maximum battery voltage and you start hammering nails in the coffin of your battery, the higher/the faster. Smile

Does this apply even if there is a trickle load, such as the Q8 switch for e.g. ?

I guess there is a market for a cheap device that will drain a specific amount of capacity from a fully charged cell for longevity, does such a thing exist?
I wouldn’t mind taking a 3000mAh 30Q, charging it fully, and then plugging it into a pre-programmed 200mAh drain (1/15) if I knew it would double the lifespan of the cell. I couldn’t be bothered to do that though if it meant making calculations and setting a timer.

Beam me up!

snakebite
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replace the ultrafires now. they are junk at best and potentially dangerous at worst.
i always let a load of cells charge fully to ensure they are all full.
that way if i use them in a multi cell light they get balanced out.
i would not bother to top a cell used for a few minutes unless it is used for an integrating sphere test and i need to eliminate any variables from the cells state of charge.

Barkuti
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Zulumoose, a trickle load is just a small load and so the drain should be interrupted by some means unless an over-discharge is preferred (at some point in time).

I can understand your newer concern. The easiest point of view to embrace is to minimize cell/battery time at elevated voltages, something as easy as fully charging cells just before usage and not after. Also, the LiFePO4 setting in some chargers is adequate for cell storage.

For a more advanced perspective, a DIY cell charger with DC-DC CC/CV modules, or just keep an eye on the cells being charged with a watch and a voltmeter. Smile

 

Cheers 

gauss163
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Barkuti wrote:

BU-808: How to Prolong Lithium-based Batteries @ Battery University

In essence: above 14/15th of maximum battery voltage and you start hammering nails in the coffin of your battery, the higher/the faster. Smile

With regards to potential battery damage caused by low state of charge, I believe most information is a busted myth. Briefly after battery management cut-off most cells will end up lieing well above 3V, at these levels damage, if present, is for sure minimal, at least compared to high voltage stresses.

Why do you believe low-voltage stress is a “busted myth” when many reputable scientific studies prove otherwise? (e.g. see the Wöhler curves from the last study I discussed here).

Also I highly recommend against relying on information obtained from pseudoscientific sites like Battery “University”.

Barkuti
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gauss163 wrote:

Why do you believe low-voltage stress is a "busted myth" when many reputable scientific studies prove otherwise? (e.g. see the Wöhler curves from the last study I discussed here).

Also I highly recommend against relying on information obtained from pseudoscientific sites like Battery "University".

The “busted myth” part comes from having heard many times people taking care not to under-discharge their devices (smartphones, tables, etc), something which is quite difficult to attain when the actual loaded battery voltage of them is still fairly high when their software shuts down the stuff because of low battery condition. Nice to see that data anyway, I may recharge just a lil sooner now. Smile

I have nothing against the information I've gathered from Battery Universe. Let me tell you, too, that each one us is a creative force in itself and thus the reality we project is different, i.e. we're not objective observers.

 

Cheers Party