I have two Sofirn 21700s (rewrapped Lishen LR2170SD) and one of them smells. I’m assuming that I should probably dispose of it? There is no visible leakage but one definitely smells.
Both cells are almost new and so far they seem to be depleting at the same rate under normal usage. When I go to charge them there is maybe a 1% disparity between them in terms of charge.
If you can I would put them both aside for a week and measure to see if there’s any difference in the self-discharge rate. Measure after one day and then a week later. Start with them both at roughly the same voltage but not entirely fully charged. If one is an obvious problem then you’re done. At some point you should have new wrappers ready for all size batteries that you have. I would then pull the wrapper and fully inspect. If no obvious sign of corrosion then carefully clean with a slightly damp paper towel or rag and rewrap.
I have found Nitecore NL2150 HPi battery quite interesting/perplexing. Nitecore says it has a patented dual output with positive and negative polarities at both ends of the high-density battery cell. But it costs over US$40 apiece!
It is that good? If such a design is so good, are there other battery brands with a similar dual output design in the market?
It’s a proprietary design. They are basically charging you whatever they want in order for you to use the chargers built into their lights. These type of proprietary cells are quite frowned upon around here. Even protected cells are frowned upon as they add extra cost and length to the cell. There are plenty of good 5000mah 21700 cells on the market for $5 USD.
Be cautious buying a light that uses a proprietary cell. Some can also fit a regular cell and only loose the built in charging, that’s not so bad. Other proprietary lights won’t even function with a traditional cell. So if the cell were to go bad, you can’t use the light at all until you pay your big amount and receive your new cell in a week or two.
I personally don’t buy lights that use proprietary cells. Also keep in mind that these cells cannot be used in a more traditional flashlight.
I do sometimes buy protected cells, but that’s for low powered lights (less than 3A draw) I give away to friends and family. They might accidentally leave a light on and the low voltage cutoff can prevent ruining the cell.
Good to know about this special battery. It is used in Nitecore P30i, which I am looking at with great interest. Your information seems to confirm my suspicion that this light needs the special and every expensive battery; but other ordinary cell will not make it work.
Apart from Nitecore, Olight seems also to use a special battery for its “special” flashlight.
Yes, it looks like a regular battery will not work in this light. Nitecore and Olight tend to have good warranties and that probably results in their higher prices.
This is definitely a unique light with it’s remote switch capability. If you were mainly interested in it’s long range distance, I’d look at other lights in that category.
The FT03 with the new SFT40 led looks to have even more range at 1300m and is much cheaper. Link. It’s very new and not currently in stock, though. I’m sure there are similar lights that are close in size and distance, though. It is all up to you and what you want. There should be lots of discussion about the P30i in this forum.
No conventional charger will fit it, but pretty much any charger can be used if you adapt it with some wires and magnets. This is the method a lot of hobby chargers use since they don’t have molded charge bays. They are setup with wires that attach to a cell or pack. Or you can use a hobby charger.
Folomov also has a similar charger. I like Olight more because it feels like it has better quality and because it detects polarity by itself but Folomov doubles as a powerbank and is cheaper.