unprotected 10440s

[cashrip]

i just recieved a few unprotected 10440 batteries that i plan on using in my little ray s20. i know they are a little overkill for the light but i only use it for a few seconds at a time so im not really worried about it heating up too much. im pretty new to the rechargeable li-ion battery world and the only other batteries ive had experience with are the protected 18650s, which from what i understand will not let you discharge the battery past a certian voltage so that you dont ruin them or make them unsafe. as for these 10440s, what voltage should i be trying to not let them get below? ive heard that if you charge them when they get down past a certian point that they may explode :duh2:

 

[flashflood]

i just recieved a few unprotected 10440 batteries that i plan on using in my little ray s20. i know they are a little overkill for the light but i only use it for a few seconds at a time so im not really worried about it heating up too much. im pretty new to the rechargeable li-ion battery world and the only other batteries ive had experience with are the protected 18650s, which from what i understand will not let you discharge the battery past a certian voltage so that you dont ruin them or make them unsafe. as for these 10440s, what voltage should i be trying to not let them get below? ive heard that if you charge them when they get down past a certian point that they may explode :duh2:

I don't let mine get below 3.6V. That's arguably over-cautious, but: since both the battery and the light are unprotected, and the battery doesn't mind being recharged frequently, why not?

Incidentally, I've been lusting after the S20 for a while now -- how do you like yours? Do you have any other 10440 lights to compare to? I've got a couple of iTP A3 EOS running 10440, which I am very happy with, but the Ray S20 looks really nice.

 

[rich297]

Like flashflood, I recharge my batteries before they get below 3.6 volts. However, research that I've done in the recent past indicates that you can discharge down to 3.0 volts without damage to the cell. Discharge below 3.0 volts, you should replace it. I've also learned that consistently recharging a cell well before it drops to that 3.0 volt threshold will prolong its useful life.

 

[45/70]

+1 to both previous posters comments. Ideally, I prefer for the open circuit voltage (no load, rested voltage) of all my Li-Ion cells to go no lower than about 3.7 Volts and 3.8 volts is even better. There is no disadvantage to "topping off" Li-Ion cells, so why not prolong their life by giving them a charge a bit more often? Of course, if you really need to drain the cells further, in an emergency or whatever, it's there if you need it.

Dave

 

[beerwax]

how do you know, with an unprotected battery and light, when its time to recharge. ? do you just check the voltage before recharge and if its too low discard the cell? flashflood you should check the marketplace.

 

[rich297]

how do you know, with an unprotected battery and light, when its time to recharge. ? do you just check the voltage before recharge and if its too low discard the cell? flashflood you should check the marketplace.

I keep a voltimeter next to my charger. Without exception I always check voltage both before and immediately after charging.

 

[flashflood]

how do you know, with an unprotected battery and light, when its time to recharge. ? do you just check the voltage before recharge and if its too low discard the cell? flashflood you should check the marketplace.

I check batteries pretty often, and recharge anything that's below 3.8V. With that as a habit, the lowest I've ever measured is 3.5V.

BTW, check the marketplace for what? The rayn60 sales thread? Or something else?

 

[rjhooper]

how do you know, with an unprotected battery and light, when its time to recharge. ? do you just check the voltage before recharge and if its too low discard the cell? flashflood you should check the marketplace.

The LF2XT has a voltage check feature. this is the best/safest sollution for a unprotected 10440 in use. Too bad they dont make 'em any more :sigh:

 

[WillyB]

I check batteries pretty often, and recharge anything that's below 3.8V. With that as a habit, the lowest I've ever measured is 3.5V.

Would that same advice pertain to unprotected 18650's also?

 

[beerwax]

I check batteries pretty often, and recharge anything that's below 3.8V. With that as a habit, the lowest I've ever measured is 3.5V.

BTW, check the marketplace for what? The rayn60 sales thread? Or something else?

just that thread - in case you missed it. but i can see you didnt.



i reckon if i buy 4 10440 i will have killed them all in 2 weeks. and then theres the chance of finding one paired with an alkaline in a remote control or sitting in the dumb charger . i really want to fire up my rays20 (and others). hmmm, is it time to cross over to the dark side.

 

[rich297]

Would that same advice pertain to unprotected 18650's also?

Yes, it would. And protected cells as well because protection circuits are not infallible.

 

[flashflood]

just that thread - in case you missed it. but i can see you didnt.

Ah, OK -- thanks.

i reckon if i buy 4 10440 i will have killed them all in 2 weeks. and then theres the chance of finding one paired with an alkaline in a remote control or sitting in the dumb charger . i really want to fire up my rays20 (and others). hmmm, is it time to cross over to the dark side.

Once you've experienced 10440 in an AAA light that can handle it, there's no going back. It more than doubles the output of an iTP A3 EOS. Over 200 lumens from something the size of your pinky!