Universal cell cradle for hobby chargers?

I was wondering if anybody knows of a cell cradle with a spring tensioned sliding negative contact similar to what a Nitecore Intellicharger i4 uses that could have leads soldered to it for charging with a hobby charger.

I love my hobby charger for all of it’s features and configuration options, but I also love my Nitecore Intellicharger i4 because it accepts almost any battery and is just easier to deal with than alligator clips and magnets. I know I can make a sliding battery holder out of a vice grip and some brass screws, but I’m really hoping there is a universal battery carrier out there I can use.

Any suggestions would be greatly appreciated.

Maybe you could add banana sockets to your i4 to use the bays? I wonder if there are switchable sockets to isolate the i4 circuitry.

It is possible to solder neodymium magnets to your charger output. NOT MY PHOTO (I’ll never use an ultrafire cell lol) but it shows what I’m talking about. Of course, even though I LOVE my hobby charger too, with this set up, you can only charge one cell at a time. If you have the appropriate balance adapters, you can charge multiple cells in series. THIS BLF thread might be useful.

I have this
http://www.cnqualitygoods.com/goods.php?id=1546
Ripped out the electronics and soldered two wires on the contacts with bananaplugs on the end.
This cradle charges the 70mm long Panasonic protected 16340s and even 26650… All with the correct current I need.


I too use the magnets works fine also with protected cels, the first time I tried to solder the neodymium magnets them lost the magnetic field, use the flux and dont heat them too much

or like said Werner buy and mod that kind of cheap chargers

When soldering the magnets, I 1) make sure the iron is hot ie, on for a good 10 mins. 2) Flux would be ideal (but I don’t have any) so I scrape off the chrome surface of the spot where I’m soldering to to reveal a copper sub-surface. 3) Put a nice glob of solder on the wire 4) Stick the magnet onto some metal surface which in my case is a steel foot long ruler. This conducts heat away from the magnet quickly. 5) put a small blob of solder on the magnet where I’m going to solder to 6) melt the solder blob on the wire, bring wire to magnet, make sure both blobs melt together, then blow the magnet to cool it off. Total time to melt blobs together is about 4 seconds if so much… At the end of it, I put a small blob of plain epoxy over the spot where I made the connection to 1) keep my fingers away from the solder and to 2) strengthen the bond. (the chrom surface is thin and pulling on the wire to remove the magnet from cells etc can tear it off.) which reminds me: 7) Try not to pull on the wire to remove the magnet from surfaces. Pull on the magnet. :slight_smile:

I was kind of hoping to avoid gutting a cheap charger like Werner did, but if that is the only option out there for what I am looking to do, I guess I will just have to bite the bullet and do it.

Thanks everyone!

I have searched and searched and searched in vain for a ready made, high quality low resistance universal cradle for a long time! There are several threads in cpf about this issue and some here as well and the best solutions in a cradle form where either modding a voltcraft holder (tedious) or using multiple clamps with high quality wires and copper contacts (BULKY!)

In the end too much effort for little return unless you charge batteries all day long for a living.

For LIPOs I use my hobby charger and concluded on the magnet solution and you can also make balance leads with magnets at the ends. What I have been playing with lately is to come up with a solution that does not require any magnet soldering and this is what I'am thinking:

I use TWO magnets in each crocodile, one small that can fit inside the mouth and one outside that is there to increase the magnetic force or for use with button top batteries.

For the negative poles the battery touches the crocodile metal directly (where the wire is soldered) with the magnet only acting as a force. For the positive pole the magnet has to touch the button top either from the outside or the inside.

For the main power leads it works like a charm with very little resistance even for NiMH but that is for one battery charging at a time. The next step is to find copper crocodiles to use for the balance leads and make them swallow the magnet in the same way. I have tested these in between two batteries in series and the hold very nice.

Since I am also using e-cigs I charge LiPos everyday but 99% of the time single cells. For some lights I need 4 at a time hence the solution I am suggesting above. When I am in the mood and have time I will fabricate it and present it here but meanwhile someone else might go for it.

Finally, for NiMH I decided on a MAHA 9000 and I am done with it. If I need more than 4 batteries charging at a time I will go for another MAHA.

That is a good idea with the magnets. I will do that once my soldering iron gets delivered.

I’m thinking buy a cheap charger and gut, magnets seem like they should not work even if they do. :wink:

Magnets work quite well with a single cell but they can get fiddly when you’re trying to balance charge two or three cells. Some cells have non-ferrous metal located at the postive end. They can be difficult because the magnet wants to go to the perimeter of the cell where the ferrous cell case is.

Yeah my button top MNKE 3500mAh 26650’s have non-ferrous button tops. I have to use a clip on the positive terminal.

I think one of the 99 cent (when on sale) 6” plastic clamps should work without much effort. The kind you squeeze a grip to move along a bar, with a couple plastic pads on the arms. Rig a set of leads to the pads and ready to roll.

Yup, that’s what HKJ illustrated in one his tutorials. It will work well with one cell. More difficult with two or three though.

I just buy the cheap battery holders from fastteck and make up purpose made serial cradles for my different configurations. It allows me to charge in series with the battery balancer so you can charge multiple batteries in the same sime as single cells. for small single cells i typically use the magnets

here are a couple that i made:
!!

I had such selfmade cradles first.
These cradles are to short for the 70mm protected cells, also the spring material is bad and the whole thing gets a bit “deformed” while soldering, as the plastic tends to melt easily.
But you can get the bare cases of usbpowerbanks from fasttech too, I have a two cell case which has huge springs which could be shortened…

Also it isn’t possible to detect the single cell capacity when discharged in multicell configuration. The only good thing is that you can charge the cells really fast with decent current.

I still wondering why no manufacturer makes a i6 style cradle(maybe even 5mm longer) with bananaplugs and balancer cable for hobby chargers ….?

You could buy these universal chargers at harbor freight for pretty cheap. Or even online.

I turned this:

Into this:

Build thread here: https://budgetlightforum.com/t/-/7791#node-9163

Too short these standard battery charger are, my padawan…

Also it would be perfect if there were more bananaplugs on it for every count of cell e.g. If you only want to charge 2 cells…

There are balance wires, you can charge 1 up to 4 really. The banana plugs just provide the power.

You'll need conductive dummy cells in the remaining slots when charging less than 4 cells. Otherwise there's OC.

Don't know what the charger thinks about shorted balance connectors though.