Protection randomly tripped?

Batteries and Chargers Rechargeable Batteries
21

Yea, protection on the positive end is not common. I believe eagletac uses it on some of their batteries too.

I wouldn’t suggest trying to charge it up fully but you could give it just a little charge. Just to get it up to 1-2v then see if it still discharges back to zero quickly. That would point to an internal short. Whereas if it can now hold it’s level then it could have been a short in the protection pcb. Be aware that any charging of this battery is dangerous. There is the risk of venting toxic gas or venting with flames.

22

I would try to charge it, but my better judgement says not to. It’s not worth 3rd degree burns for a $7 cell. Unfortunately I’ll have to replace them as a pair though……

23

Pic

The little torn spot is not a short, the board was potted and one of the caps tore off when i removed the rubber potting compound.

I apologize if the sizing of the pic is incorrect, like I said, mobile only….sucks hard.

24

This is my issue with Protection. It gives a false sense of security. The best avenue is making sure the light has a way via the driver to either indicate a low battery or completely shut it off. If you must have protected batteries, look for batteries with the Seiko protection boards. Cost a little more but well worth it IMO.

25

I was under the impression that the olights did indeed use seiko pcbs, but as you can see, it clearly doesn’t.

26

Where did you buy the battery from? Any chance of a close-up of the pcb so that it might be identified?

27

Right click, open image in another tab. It will be a larger photo.

28

Thanks chadvone :smiley:

29

Welcome, I just learned this. It will also make a GIANT photo page size. There are a few giant photos on BLF :smiley:

30

You’ve got more common sense and restraint than me Lightgecko, i would just have to know! ps, this cat’s been singed a few times :smiley:

31

Here’s the PCB. It is the button top. I took these with a cheap aspheric lens to get my phone to focus that close, sorry for the distortion.

32

Are you able to read the markings on the chips?

33

There aren’t any markings, either they were rubbed off by the manufacturer or they came off when I peeled the board out of the rubber potting.

34

Then we don’t what they are, they could be seiko.

Chip markings are laser etched. When oil or other material gets on the chip then the markings can sometimes become difficult, to almost impossible to read. I’ve seen chips I could barely read under high magnification even when trying every viewing angle and light angle. Some chinese companies do obliterate chip markings when they fear others will try to copy their design. But there seems to be almost no reason for o-light to do it here. The rubber potting probably just made the markings hard to see or almost impossible.

35

I have several ncrb and all say “made in Japan” and the datecode is different than on your pic.
But mine are several years old maybe there were newer ncrbs on the market…

This is what a short search brought up:
http://www.amazon.com/Panasonic-NCR18650B-3400mAh-Rechargeable-Batteries/dp/B00MAVEDMS

Check the description and reviews…:frowning: