6-SLOTS 18650 Li-on Charger

[Scorpiolyons]

:candle:Just for a marketing survey:

What do you think if there is a six slots 18650 Charger for sale in the market? Would you mind using this kind of charger to charge six pieces of 18650s at one time WITHIN 3-4 hours?

 

[amigafan2003]

I'd just use a hobby charger to do the same thing.

 

[monkeyboy]

That would be a great idea. I would consider buying one of those. There would be some requirements though:

1) each channel must be fully independent i.e. no charging multiple cells in series or parallel.

2) Must make sure the cell voltage doesn't go above 4.2v no matter how long it is left on the charger.

This would be way more convenient than using a hobby charger. The hobby charger requires a balancer for a specific number of cells.

 

[amigafan2003]

This would be way more convenient than using a hobby charger. The hobby charger requires a balancer for a specific number of cells.

It doesn't if charging in paralell.

 

[monkeyboy]

It doesn't if charging in paralell.

If you're charging in parallel, the cells need to be in the same state of charge to begin with otherwise you need to leave it on for a long time after terminating to balance. This is not ideal.

 

[rmteo]

If you're charging in parallel, the cells need to be in the same state of charge to begin with otherwise you need to leave it on for a long time after terminating to balance. This is not ideal.

Not so. You do need (or want to) balance the cells when charging in parallel - as mentioned by amigafan2003. Cells do not need to be in the same state of charge when charging in parallel.

 

[45/70]

If you're charging in parallel, the cells need to be in the same state of charge to begin with otherwise you need to leave it on for a long time after terminating to balance. This is not ideal.

When charging Li-Ion cells in parallel, the voltages should be within 0.5 volts of each other. That's really pretty easy to do. I charge 3x18650's in parallel. They are used in a 3s light, so when I put them in the charging cradle, they are, at worst, +/- 0.1 Volt, usually +/- 0.05 Volt, or less.

Dave

 

[Mr Happy]

If you're charging in parallel, the cells need to be in the same state of charge to begin with otherwise you need to leave it on for a long time after terminating to balance. This is not ideal.

I think this is true for the most part. It takes a certain amount of time for the charge on each of the cells to equalize, and the more unbalanced they start out the longer it will take for equalization to complete.

 

[rmteo]

Let me ask hypothetical question. If you take a discharged cell and parallel it with a charged cell, would it take longer (or less time) to charge as opposed to charging it on its own?

 

[45/70]

I think this is true for the most part. It takes a certain amount of time for the charge on each of the cells to equalize, and the more unbalanced they start out the longer it will take for equalization to complete.

While that may be true with NiMH/NiCd, I don't believe it applies to Li-Ion chemistry, or at least, if it does, it's to a much lesser degree. I think that is one of the reasons parallel charging is suitable for Li-Ion cells, and not nickel based cells. But hey, you're the chemist Mr H!

Dave

 

[vali]

I think 6 slots can be too many. Probably I am just used to 4-slot NiMH chargers, but I find that amount is what most folks tend to need.

For me a good Li-Ion charger should be something like the Maha C9000, but for lithium, plus a couple of additional things: You should be able to select chemistry, not only Li-Ion, and be able to charge not only 18650 cells.

Of course, that thing would be too expensive, and a proper reliable charger with craddle is a good idea too (but I really LOVE knowing the real capacity of my cells). Right now we only have 3 options: A cheap and unreliable charger up to 2 cells (DX thing or so), a reliable but pricy and single-slot charger (PILA) or get a hobby charger (and a PSU and do a bit of DIY). Adding a good alternative is always good.

 

[monkeyboy]

Well just from experience, I used to charge 2 x 18650 li-ion in parallel in the DSD charger and even cells used in the same light would sometimes end up out of balance on termination but leaving them for a while would balance things up. I found it a little inconvenient having to measure each cell with a DMM at the end of every charge.

 

[TriChrome]

I would personally be interested in just the cradle/dock/holder for the 18650 batteries, with a balance tab.

I have a great hobby/RC battery charger that will charge them properly, but I have no way to hook-up multiple loose cells to the charger.

 

[rmteo]

I would personally be interested in just the cradle/dock/holder for the 18650 batteries, with a balance tab.

I have a great hobby/RC battery charger that will charge them properly, but I have no way to hook-up multiple loose cells to the charger.

You can make one with these http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=393250&k=18650

Well just from experience, I used to charge 2 x 18650 li-ion in parallel in the DSD charger and even cells used in the same light would sometimes end up out of balance on termination but leaving them for a while would balance things up. I found it a little inconvenient having to measure each cell with a DMM at the end of every charge.

With a right charger, this is not a problem.

 

[Benson]

6 slots would be great, but I'd be much more impressed by one with even two or three slots that will accept any of 25500, 26650, 26700, or 18650, with no occlusion of adjacent slots when charging the big cells. Bonus points for switchable voltage (4.2=LiCo/LiMn, 3.8=LiFe), and better yet if it takes IFR32600s as well, although I don't have any yet.

If it's a proper multichannel setup, three 2-slot chargers shouldn't cost much more than a single 6-slot, and a lot of people only need 2 or 4 slots capacity.

My main charge bank is currently 6 2-slot 18650 chargers in a row -- 5 used to charge 5x26700 (can't use the other slot, so one per charger), and one for a couple 18650s or 25500s (with magnetic leads).

 

[monkeyboy]

With a right charger, this is not a problem.

Please explain how a better charger would be better at balancing cells in parallel. I mean pre-termination that is.

 

[rmteo]

I have 3 of the Accucel-6 chargers (pictured above) and one of these (10A charge/20A discharge) and they all get the cells balanced upon termination when charged in parallel. Don't know why your DSD does not do so.

 

[ptolemy]

I'd want a variable charging cradlle...not just for 18650 size, but from 18650 to 26650 (ie make channels wider)

rest is cool:)

but to charge 6 x 18650, u might wanna do 10a? and if u do 26650, u can go 15a, so ya fun time

 

[GarageBoy]

dont care about the slots...just want a nice cradle for the batteries. All hobby chargers have a balancing feature when charing in series

 

[kramer5150]

No interest, unless it were less than ~$55

I just charge my 18650 cells in parallel in a DIY tray with a CC/CV hobby charger. If there is one cell considerably more discharged than the other, I just charge it by itself in the same tray. I can make a tray for under $5-6. I am not even going to try and explain the technical aspects or just how this works. All I know is that it does. The charger never goes past 4.2 and the cells are all equally 4.17-4.18 hot off.

I easily manage all my 18650s this way. I am almost finished making a 4P tray. My charger peaks at 5A, so that would be hitting each cell with 1.25A, so charge times should be around 2 hours.