26650 recommendations

[Nice65]

They were at 4.1-4.2 V with 0.5 A. They were charging for about 9 hours and whenever I checked, it was 0.5 A. I'll discharge them and retry as the Ecolux owner suggested. If this continues I'll discuss what to return, whether it's the batteries or the charger.

What was their starting voltage? Sounds like everything is working fine. The charger is doing what it’s supposed to do when the batteries are full, trickle charge. Very often I can only get 4.1V into my batteries, so it’s normal it’s slowed right down at the end of the cycle.

Whack them in the torch and run it up for a bit, then check them again, especially looking that one isn’t warmer than the other. But in honesty, I reckon you’re good to go with those.

Apologies for the weird edit, I hit delete by accident and it’s dumped half my post in a quote box.

 

[Jared]

Is the charger only getting 0.5A? Because that's suspiciously the USB 2.0 maximum amps.

 

[hughtrimble]

Is the charger only getting 0.5A? Because that's suspiciously the USB 2.0 maximum amps.

A good call but it's being fed by a 100 W charger and a 240 W USB C cable which powers my laptop etc. so no issues there

 

[Jared]

I wonder if the charger is actually capable of negotiating USB PD.
I'd try a dumber USB C power source.

 

[Nice65]

I wonder if the charger is actually capable of negotiating USB PD.
I'd try a dumber USB C power source.

So would I, I bought the XTAR plug when I got my charger, but it works fine on an Anker IQ 4-way USB which is what it’s plugged into now.

 

[hughtrimble]

So would I, I bought the XTAR plug when I got my charger, but it works fine on an Anker IQ 4-way USB which is what it’s plugged into now.

I wonder if the charger is actually capable of negotiating USB PD.
I'd try a dumber USB C power source.

Hi both,

Yes indeed, to check it wasn't the charger I tried other power sources too, and still the same situation. The dials show 2 A for a very brief moment, drop to 1 A for a maybe a second, and then drop to 0.5 A seemingly permanently, this happens using a variety of power sources.

 

[hughtrimble]

Discharged the 26650s and both have been charging for a few hours now at 0.5 A, 3.5-3.8 V. No idea how to tell if it's the charger or the batteries at fault here? Fault being a strong term, but this combination is not charging as the specs would suggest from either.

Put in some 16340s in earlier and likewise, started at 2A but immediate drop to 1 A then a second later 0.5 A.

 

[hughtrimble]

They did at some point switch to 1 A charging for a while. Just takes absolutely ages to charge them up, and that isn't really what I'd hoped with this set-up.

Nice extended boost to the runtime on my dive torch though, about 2hrs30 on high (2k lumens) and then at least another 30 mins on medium (1k).

 

[Nice65]

Keep them topped off if using regularly or around 3.8V for long storage. If you’re totally discharging then they will take an age and it’s not good for them, though I’m pretty sure you’ll know that.

 

[hughtrimble]

Keep them topped off if using regularly or around 3.8V for long storage. If you’re totally discharging then they will take an age and it’s not good for them, though I’m pretty sure you’ll know that.

I did about the total discharge, but not about a good storage voltage. Cheers! If I'm in the water for 2+ hrs something has gone very wrong.

Looks like the protection circuits will constantly drain them too, but should take a while?

 

[Nice65]

I did about the total discharge, but not about a good storage voltage. Cheers! If I'm in the water for 2+ hrs something has gone very wrong.

Looks like the protection circuits will constantly drain them too, but should take a while?

I’m guessing but I reckon it would take ages. I have a protected 18650 in a SW/FM pocket radio in the camper, doesn’t seem to lose much over months.