As stated in the the topic, I am interested in both 1x18650 and 2x18650 (parallel) battery cases for headlights. I’ve been searching but can find anywhere where I can buy the cases only. Anyone know where I can get’em? Cases similar to the two below are of interest:
1 x 18650:
2 x 18650:
not exactly the answer, but information none the less: I have the headlamp with the same battery case as the one on the bottom picture, and it is hard plastic from the side facing the back (with the LED inscription) and rubber on the front side (touching the back of your head). The rubber is quite soft and will bend easily when wiggled while on the head or helmet, and hence lose waterproofing seal. It also has a charging port connected directly to the batteries, plugged/sealed with with rubber plug. I’d personally rather have a rigid battery case with rubber seals, although this was a part of a budget buy, the entire headlamp cost around $20 with low quality holyfire batteries and charger.
I don’t have what you are asking for. Are you looking specifically for a battery holder which attaches to the head/helmet with a strap?
In the meantime:
I’m on the same sort of quest… I’ve been using mpd holders (via digikey) (alternate by keystone that might be more available overseas — digikey is a b@stard for overseas shipping) that have been wrapped in a clumsy neoprene sleeve. Problem with these is that they don’t like really long or really short cells.
I’m thinking about bodging together something out of a bit of irrigation pipe, or getting some time on a 3d printer… (though now that I think about it, it seems like someone must have done the 3d printer thing and posted their files).
I’d rather have rigid too, preferably water/rain proof. I only linked to these images to give a rough idea of what I’m looking for. However, if only these soft ones where available I’d take them anyhow.
Yes.
I have one since a long time, and have used it too. But for head/helmet use it’s too big.
Yeah, If I don’t find what I’m looking for I might have to do a DIY solution like this, at least for the 1 x 18650 solution. 2 x 18650 might be a little harder. Was hoping to avoid it though.
Yeah, DigiKey is expensive with overseas shipping. I managed to fill the order out to get free shipping, don’t think I can do that again. If you find a decent solution, please let me know. I’ll do the same.
Many of us have been looking for a good 2 cell battery holder, so I asked Dora and May tat GearBest to find out if they can get the Fenix BA4C 2 Cell Battery Case seperately. May just told me they can if there is interest.
The only issue is the need to swap the existing connector with the correct connector since it has a male connector rather than a female. I doubt they will swap it for us.
is there interest in this case? There is some interest on MTBR http://forums.mtbr.com/lights-night-riding/fenix-ba4c-case-found-946922.html
That looks nice.
I’m not immediately interested, but it’s possible that I’d purchase one sometime down the road if they were made available.
replied in the MTBR thread so I don’t get double-counted
I might be interested but not a MTB member. The other day I was actually browsing just for that box and I found a German site that carried them at 20 Eur + shipping and I thought that was just too much for an empty battery box. At half that price I’d get one though.
I’d be interested in a case or two.
there are also powerbanks and their cases being sold separately as DIY kits
for example…
http://www.fasttech.com/products/1424/10004458/1341102
All the ones I’ve seen, including that one, are too big. I just want a battery case, not that extra stuff that makes them larger than the need to be (for my purpose).
I have not found any which could be useful as a 2s1p power source. A power bank normally uses a circuit to boost 3.7v batteries up to 5v output. This thread is about a decent 2s1p holder for helmet/belt mount which can output 7.4V and thus be used for typical bike lights. It is surprising that these boxes are so hard to find, whereas 2s2p boxes are quite common.
It is easy to find the holders, even with protection circuit (like this one ) but not in a decent box where you can change the cells on the go or charge them elsewhere. The fenix box is one of the few, and probably the most compact one.
Another alternative could be this Helmet Battery Case
Here is a review at cpf with some better pictures.
pricey! £13.90 plus £4.23 shipping within UK
you confuse me 
the thread is about a 1s2p case for headlamp. Where do you see that it needs to output 7.4V and be used for bike lights?
I was sugesting usb power boxes just as a donor of the casing, since they are plentiful in design and size with low price.
the bare, non-encased holders are out of the question here, the batteries need to be fully encased, if not waterproof.
Thanks, it’s closest to what I’m looking for so far (although it has unnecessary space between the two cells). It is however a little too pricey. I’m sure one shouldn’t have to cost that much if bought from somewhere else.
If I can find one that’s not got a lot of extra space I might get one. They are flat so adding headband straps shouldn’t be an issue.
¡and big!
I am about to do surgery to my magicshine headlamp battery pack, which is just perfect in shape and size except it is completely sealed. I don’t know how to start prying and I am afraid to break it:
¿Any suggestions on how to start?
The magicshine box is on sale for about 29Eur with two 2200mAH high quality batteries. If I can manage to pry it open (non-destructively) and swap the batteries it would be just perfect. The fenix BA4C box looks pretty cool, but the availability seems quite limited and the best price that I have found is 11.50 eur (+ 6 shipping from the Checz Republic). That is only for the box, no clips/straps/holster.
Uppps I am afraid that two different threads are mixed then. You are right the first posting was about 1x or 2x “parallel” boxes, but after the post on Fenix and helmet battery case we have intermixed it with analogous 2s1p boxes that can be mounted on helmet for using bike lights. Many of us here and at MTB forum have shown interest in these, which are of course 7.4v output.
For a decent 1s2p box, someone also suggested this one at fasttech . A little procey for a box, but you also get a cheap headlamp for free 
another cheap option to scavange the box itself