I recently acquired some 4.35v, 2800mah 18650’s.
I didn’t believe they would actually be 4.35v (my source for info was alibaba :~ )
but they were all at 4.24 volts when I pulled them… so they are likely four three fives?
opinion on that?
Also, is there any added benefit to charging them to 4.35v? I recently got a 2.1 dreamcharger, so I guess i could dismantle it and flip it to 35… but for what? you reckon it’ll push my light really that much harder?
In single cell lights you'll get longer runtime in regulation (or, higher initial current if direct drive), everything else being equal. For multiple series cell lights where even the lowest minimum voltage is high enough to stay regulated there's no benefit.
If you don’t charge them up to 4.35v, you won’t get the claimed capacity out of them. I want to say that you lose about 10% charging them up to 4.20v, which is fine if that’s how you want to roll?
I have some LG D1 3000s and E1 3200s and bought an Xtar VP2, just for them.
Chris
I am confused, is the voltage applicable to all li ion
or specific brand?
Specific models, not just brands. There are 4.2v, 4.3v, & 4.35v cells. You can charge a 4.3/4.35v cell to only 4.2v and you just get a little less capacity but longer life... try charging a 4.2v cell to 4.35v and if you're lucky you just get drastically shorter life. If you're unlucky you'll get an explosion and/or fire.
LG and Sanyo make cells that can be charged up to 4.35v. These hotter cells ‘can’ hold a higher voltage over time and might perform better in certain lights.
Samsung makes a cell that can be charged up to 4.30v, so you get a bit more voltage out of it than typical 4.2v chemistries.
You need a charger that can charge up to 4.35v, to utilize that extra capacity. Since we don’t find many 4.30v consumer chargers on the market, that Samsung can be somewhat of an issue. While 4.35 chargers are ‘probably’ within the ‘+/- .05v window’ for the 4.30v cells, if your charger overcharges, you might kill the battery sooner, rather than later.
Chris
Fully charged 4.35V batteries perform like a 4.2V battery that has incredibly little voltage sag.
If you only charge them to 4.2V, they should last a lot longer due to a partial charge putting less wear on the battery. Of course that depends on you not fully draining the batteries, which causes lots of wear too.
I'm actually about to order a bunch of 4.35V batteries and mostly using them with a partial charge. The flashlight it's used in will be kept at a "full" 4.2V charge all the time, and I'm hoping these batteries last a lot longer due to the partial charge.
Ehhh…they’re ~$6.50 per cell, for my LG D1s/E1s and I’m not cycling them but once every month, if that, so I’m not worried about killing them via 4.35v charging. They’ll probably go stale long before they crap out on me because I’m charging them up to 4.33v (VP2.)
I guess if you charge them up everyday, you’re using a lot of them and money is an issue, you might want to only charge up to 4.20v, but I doubt many of us are paddling that boat?
Live life in the fast lane. All the cool kids are doing 4.35v these days, lol.
Chris
I used to keep all my batteries fully charged. Many were never used, but leaving them fully charged put a lot of wear on the batteries.
so how will we know which batteries do that voltAge?
is it listed in the wrapper that they can be charged
that high?
Is it expected all china cells to have 4.2 as limit?
I don’t know of any Chinese made cells that handle 4.30v, or 4.35v.
http://lygte-info.dk/review/batteries2012/Common18650comparator.php
Use HKJ’s battery comparator in the above link. There are two ‘pull down’ windows that let you select your cells. Click on ‘individual tests’ to see each cell’s performance, in detail. In the large menu, you’ll see 4.30v and 4.35v, denoting cells that were charged up to that voltage.
That should keep you busy for about 6 months, lol.
Chris
I discharge my ‘spares’ down to ~3.6v and place them in a ziplock baggie and then into the fridge, if I’m not going to be using them within 3 months. I have about 20 of them in there now, lol.
Chris