Is there any reason I shouldn't buy these http://www.kaidomain.com/product/details.S009747 ?
Also is there any reason I shouldn't buy non-protected cells? They will be going in a jet beam BC40 and solarforce l2s and l2t. I though about some Xtars but I have 2 Trustfire flames and a cheap charger that came with them. The charger is actually quite good but the trustfires are very tight and the Xtars are longer. So instead of buying a new charger I thought I would get the Sanyos.
Marc.
You shouldn't use unprotected cells in multi-cell lights (such as BC40). Using them in single-cell lights (like L2T) is fine.
Good cells, with a little care no problem in multi cell lights IMO. The ones I have are my best matched cells. I'd sooner use these than *fire or some other rubbish, protected or not.
…but he was thinking about protected Xtar’s (which are same Sanyo cell but with protection added) :Р
.... yes but the Xtars prob won't fit so it's protected shorter cells like the *fires or unprotected Sanyo's :p back at ya lol
Yeah thats the problem really. I would buy the Xtars, but I'm not sure they would fit the charger.
If I make sure the cells are evenly charged I should be OK shouldn't I? And don't mix them with my trustfires.
Marc.
You should theoretically be OK providing your flashlight has low-voltage protection.
I use unprotected cells with my custom built 3 mode 2x18650 light with Kaidomains driver. They discharge parallel and I haven’t got any problems so far. To be safer, you can exchange the for and aft cells after a while. The cell closer to the head heats more and this my unbalance things.
Yes over discharge is the main issue, but even if you do take them too far you should only end up with scrap cells if you test when removing them. The main issue I believe is once recharging a cell that has been taken too low. Lots of chargers will not allow charging of an over discharged cell tho.
If they discharge in parallel, that’s same as single-cell cause reverse-charging is impossible in parallel usage. But in series usage nothing prevents cells from getting reverse-charged after getting emptied.
They are great. Get them and take care of them.
Does anybody know what the working voltage of the BC40 is? I have tried searching but all I can find is a review saying it is somewhere between 5 and 12v.
I know the drop-ins in my solarforce's work on 3 fresh eneloops but not 2, which means they wont run at 2.8v so that should be fine for an unprotected Sanyo.
Marc.
Well if Snoop dog says get them, then thats enough for me!
By the way how did you get your user name?
Marc.
Well, BC40 has a low voltage protection at 5 or 5.5v anyway. So even if a cell is discharged further than the other the circuit will never let the voltage go beyond the boundries of reverse charging.
Lets say the both cells start at 4.1v. Both should have the same start voltage, this is what the consensus says. But let's say the weaker cell has 10% less capacity. At the end of its capacity the other cell should have spent its 90% already. So it should be around 3.0v already. The other cell can still touch down to 2v for a few seconds but would recover fast as the light turns off. It's voltage is never meant to drop below 2.5v If both cells are well balanced from the start.
I'm Lang and the C,J&L are the kids first initials. I always want to make a cool user name but that one has been with me since Al Gore invented the internet.
Lang your first name or last? The reason I ask is, I to, am a Lang!
Marc.
So, are you saying all should be OK and I won't damage the cells?
Appreciate the replies by the way, Marc.
Keep the cells charged fully before you put them in the light and you should be safe. And never run any further than the point the light dims.
OK, good stuff. I have just found a data sheet on the cells saying you must not go below 2.3v. So I don't imagine we will get that low. I think the BC40 only works on high with 6V. It would be go if Jetbeam would tell us.
Marc.
marcl, cells below 2.8V are pretty much useless already, and imo its healthy not to go below that, no matter what the specs say.