How funny I am back again reading this thread 
This case looks good but is there something better now!!??
Unfortunately not that I would know. If you find anything, post it here.
2x18650 Fenix case?
Its out of stock at GB…
Bumping this thread….The solarstorm pack is currently at $6.39 now at GB on promo! I might finally get one….lol
You have to be extra cautious with this case (earlier gen). I left a pair of 25R in it over a few day without using, and one pc of 18650 got drained down to 0.4V !!!
Ah I thought it was the more recent version. Thanks for informing me.
I am not referring to that particular product ID from GearBest. I bought mine back in 2014 (gen 1 or 2). Just keep an eye when you are using it. Use protected 18650 just to be safe.
There have been many reports over at MTBR of 1 pair of cells draining but the other pair not draining (either at all or at least not evenly with the first pair). Be sure to keep an eye on your cells used in these cases!
-Garry
This is $6.39 on GearBest right now. Promo ends in 6 days. I just ordered 2.
Folks - is there something similar on the market for 4x26650 instead? The only thing I can find is 4x26650 battery pack with hard built-in noname 26650 cells. But no any case that can allow me to put & use mine own 26650 cells. Any tips & recommendations are highly appreciated, cheers!
I didn't know 6 cell version was out since Jan.
I recently received a” 2 x 26650 case”:https://www.ebay.com/i/273007284923?chn=ps, which I have yet to fully test. I expect it to be as bad as the Solarstorm 4x18650 case.
-Garry
Hi Gray, will you be testing the 6x 18650 case? Seller claim "10μA" parasitic drain this round.
I don’t have a 6x18650 case. Not sure when I’ll get to testing my 2x26650 either.
-Garry
Is there actual charging circuitry in this thing?
Or is it depending on the power supply to do the CC/CV charging ?
(Because in normal bike lights, charge control is done in the battery holder, and I can’t see any circuitry in these holders other than springs…)
wle
Not usually no. Majority of bike lights rely on the wall wart to charge with proper algorithm and cut-off (majority don’t “cut-ff” per-se, but just diminish charge current to where it reaches 0.00v). The holder MIGHT have an over-charge cut-off and over-discharge cut-off.
-Garry
the case specs do mention overdischarge and undervoltage protection..
you said:
"(majority don’t “cut-off” per-se, but just diminish charge current to where it reaches 0.00v)."
but did you mean:
(majority don’t “cut-off” per-se, but are actually simple constant-voltage controllers, controlling current to keep voltage below 8.4V )?
Nope. The voltage can be higher than 8.40v when the charge current reaches 0.00A. I THINK (I’m no expert) that one thing that plays largely into this is the “no load voltage” of the charger. Some really bad bike light chargers put out over 10v no load! The “good” (i.e. acceptable) ones put out around 8.42v to 8.45v. Some are labeled as chargers and are nothing more than a power supply thereby relying on the packs protection pcb to stop the charging process.
See the review I just posted on the ROCKBROS battery pack and included charger. There are timelapse videos showing how the charger is operating.
Also, I should have said that I’d NEVER charge the cells in these boxes! One of the biggest reasons to have these boxes is to charge these cell individually.
HKJ has also published a review on at least one of these types of chargers showing how they just “float out” to extremely minimal charge current.
-Garry