Balance Charge 2 to 12 (Any Li-Ion Type) With Magnets Simultaneously--Check This Out!

[LuxLuthor]

I have to give credit to Raoul_Duke who asked me for some of my magnet leads I used to sell here. I got to thinking of the charging of all my Lithium Ion cells and just came up with a very easy way to do it...sort of a VOILA! moment.

I have long ago mastered the technique of securely soldering wires to powerful Neodymium magnets. Now I attach 22 AWG balance wires to them, and other end comes back to a JST or Yeonho SMH250 connector which plugs right into the balance tap connector on your charger. Main charging power clips on larger 16AWG and stronger end magnets attached to end of string.

I have 9 colors of wire, so could simultaneous balance charge 4, 5, 6, 7, 8 or more cells. One of the tricks was getting the proper connector for charger from Korean company, and crimping tool.

Couple sample pix to show proof of concept.

 

[LuxLuthor]

Re: Lithium Balance Charging with Magnets--CHeck this out

I'm happy how well this works. To easily balance charge 6 or more Li-Ion cells with single charger doesn't need the cradles we were trying to work out in other threads. Here is photo of underway charging:

This works well enough to be able to charge large number of cells and have them balanced with each other. easy & cheap setup. I have got ahold of the connectors that plug into the Hyperion LBA-10 or eStation BC-6.

 

[mfrey]

Re: Lithium Balance Charging with Magnets--CHeck this out

Cool. Are you accepting orders?

I could use one for a BC6 that is capable of balance charging two or three cells depending upon the application. I was going to make one myself but if the price is right there's no point in tooling up and rediscovering what you've already pioneered.

 

[karlthev]

Re: Lithium Balance Charging with Magnets--CHeck this out

Always great work LL, nice...!


Karl

 

[LuxLuthor]

Re: Lithium Balance Charging with Magnets--CHeck this out

Also, these magnets have very strong force, so with their nickel coating, easily work with 5A charging current. The end wires are thicker 16AWG, while very low current balance tap wires only need to be 22AWG. It's not designed for use with the 10-20A fast charging the RC guys use in their LiFePO4 packs.

mfrey, as a further proof of concept (even though I used above also in BC6), I could do a 3 cell for you that would work with BC6. You would need thicker end magnet leads too? Probably $15

The funny thing about the BC6, is for some inexplicable reason instead of using the 7 pin/lead connector which is how many you need to balance 6 cells, they use an 8 pin connector, making two Neg (black) wires be joined as one. But having thought ahead, I got a bag of 8 pin connectors from Korea also.

 

[csshih]

Re: Lithium Balance Charging with Magnets--CHeck this out

interesting! mind sharing your technique for soldering onto magnets?

How much magnetism do they lose? I heard that heat gets rid of it.

 

[flasohollic]

Re: Lithium Balance Charging with Magnets--CHeck this out

I have done it very simulare excpet i only charge two as i only have pair not 4-6 simulare cells and use springs instead of magnet

http://img233.imageshack.us/img233/3205/dsc0613f.jpg

 

[LuxLuthor]

Re: Lithium Balance Charging with Magnets--CHeck this out

It is extremely easy to destroy all of the magnetic force. I think surface prep, correct solder, flux, and fast soldering are the main things. I can do it with no loss of magnetism.

I could probably have hung a 4th C cell if I wanted to go hunting for another in one in my lights....but this gives an idea.

 

[LuxLuthor]

Re: Lithium Balance Charging with Magnets--CHeck this out

I have done it very simulare excpet i only charge two as i only have pair not 4-6 simulare cells and use springs instead of magnet

There are many easy ways to do 1 or 2 cells. Also, those type of 'cheap' springs have very high resistance which cause problems if you need more than minimal charging current.

When you have a boatload of cells, and you don't want to spend all day charging, there are few options to arrive at balanced charged cells. If I hook up a 2nd Hyperion LBA-10 balance charger, I could do 12 cells at once with this technique. To give you an idea of how long we have been wrestling with this issue, you can look at this old Voltcraft adjustable cradle thread here...which are only available in Europe, and this mod was considered a major breakthrough.

More importantly, this magnet method works for any size cell that has a ferrous metallic end plate. A notable exception are the A123 Systems Inc brand of Nano Lithium Iron Phosphate cells with an aluminum can. Although they spot welded a wafer-thin ferrous-nickel disc on the end that the magnet can make contact with, I would be charging this with my own spot welded battery pack contact strips==>soldered to wires in any case with these particular cells.

 

[rizky_p]

Re: Lithium Balance Charging with Magnets--CHeck this out

wow that is a lot of 18650s to charge

it still baffles me on how you solder those neodymium magnets that came with "15.6v torch" battery pack that i bought from you without damaging the magnet it self...care to share some tricks lux?

Nice trick on charging and balancing using the magnets.

 

[Raoul_Duke]

This is exactly what I wanted....

Lux was the only guy I knew who had sussed soldering these magnets, I tried a couple, and cooked them. :sick2: So I asked Lux to see if he could Chop up RC harness kit and solder magnets onto it.

I never dreamed he would find a solution for various chargers/ connectors types etc.

Folks, I know that Lux has put quite literally $$$$'s into this project alone, and lots efffort tracking these down...So Maximum Kudos To Him

You just can't get/ find these connectors...and thats just the start, you got to get the little crimps, etc, etc.

Where Do I sign?

You are going to sell some of those connectors...Right?

 

[LuxLuthor]

LOL! I didn't really mean this to be a sales thread. Oh GOD....the pressure of delivering on sales threads!!! I mainly wanted to post this, given the hours and hours and hours many of us spent trying to figure out how to more efficiently & safely charge the larger quantities of Lithium cells. Many of were shocked that no universal balance tap

I have one of FiveMega's original Mag85's that uses 9 x 17500 Li-Ions. When I think of the number of times I waited for them to charge in two of the 2-bay DSD chargers, then two Pila chargers...when I could have charged and balanced them all at one time...I can only wish I had thought of this long ago.

Some chargers can use JST XH plastic connectors which have been at Digikey for a long time. But try and find SMH250 connectors & YST pins which a number of hobby chargers use.

 

[Bones]

I'm almost sorry to see this solution working so well.

While elegant in it's simplicity, it will probably spell the end to most of the endeavors like this one by Data that are as much art as science:

 

[Black Rose]

I am always amazed at the ingenuity and amount of effort some of the folks on this forum put into finding solutions to problems like this :thumbsup:

I think the only downside to Lux's solution would be the amount of horizontal space needed to charge cells once you get beyond 3 or 4 cells.

 

[rizky_p]

you can put the battery rest on the table, if its get too long then build a U-shape connector so the battery doesn't have to be in the straight line.

I think the only downside to Lux's solution would be the amount of horizontal space needed to charge cells once you get beyond 3 or 4 cells.

 

[LuxLuthor]

I am always amazed at the ingenuity and amount of effort some of the folks on this forum put into finding solutions to problems like this :thumbsup:

I think the only downside to Lux's solution would be the amount of horizontal space needed to charge cells once you get beyond 3 or 4 cells.

That is a legitimate point, but I got used to charging 20-30s Elite 2/3A NiMH cells with the much thinner magnets which hold them in a straight string.

However, I also developed this 6p (& made a 12p) setup which can be used to charge as a 'single' cell with large capacity.

 

[Black Rose]

Nice work Lux :thumbsup:

 

[Turbo Guy]

I only needed to charge one or two cells at a time and FMA Cell Pro will charge at up to 4A through the balancing leads so ......

https://www.candlepowerforums.com/posts/2914867&postcount=1

 

[MWClint]

I have been using the triton and equinox balancer for my rc lipos..
the equinox came with a few extra balancing leads, so i figured i'd
have a go at Lux's mod.

i did a simple 2S balancer, using 3 neo magnets.

filed an edge of each neodymium magnet, very lightly until some copper
color shown thru. dabbed a bit of flux on the filed edge, hit it for a second with the solder and balancing leads on each magnet and it was done.

charged a pair of imr 16340's and it went without a hitch.

thanks Lux for such a cool idea!

 

[3rdrock]

Re: Lithium Balance Charging with Magnets--CHeck this out

:hahaha:

To give you an idea of how long we have been wrestling with this issue, you can look at this old Voltcraft adjustable cradle thread here...which are only available in Europe, and this mod was considered a major breakthrough[/URL]./QUOTE]

I was looking for this last week.Thats funny.I want to start getting more batterys and didnt want to wait days to charge them.
Where is the best deal for a eStation BC-6 so I can get your balancer with magnets?