Low resistant clamp/holder for 18650 cells?

I've recently gotten a CBA IV, so it is time for me to do some tests on some cells that I have sitting around!


I do have on hand some of those $0.99 eBay cheapie 18650 holders, but the wires that came soldered with them are incredibly thin, and the whole thing just looks poor in general, so I am feeling concerned that it might affect test results.


Is there some good quality clamp/holder of sorts that you've used before for doing similar type of testing?


Thanks!

http://lygte-info.dk/info/HobbyChargers UK.html - check the section "How to connect the cells", easiest one is using Luminous DIY holder, but it's hard to find them for sale anymore.

Does anyone know what is this clamp that HKJ is using?

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wshyang said:

Is there some good quality clamp/holder of sorts that you've used before for doing similar type of testing?

Click to expand...

For all my test I have used this type of holder:


Here is the improved version I have used the the 2012 battery test:


The important point is that I uses separate wires for current and measurement, but this is not possible on the CBA.

HKJ said:

For all my test I have used this type of holder:

Here is the improved version I have used the the 2012 battery test:

The important point is that I uses separate wires for current and measurement, but this is not possible on the CBA.

Click to expand...

What kind of clamp is it HKJ?

Actually I am trying to figure out the brand (can't make out from the picture) and also what it is called. It doesn't look like anything I've seen around, thanks!

wshyang said:

What kind of clamp is it HKJ?

Actually I am trying to figure out the brand (can't make out from the picture) and also what it is called. It doesn't look like anything I've seen around, thanks!

Click to expand...

The topmost clamp picture is an Irwin, the clamps I am using in my current battery test does not have a name.

The wire connection is DIY. I drilled a hole through the top and bottom of the clamp and then used a screw and some brass nuts. Next time around I replaced the brass nuts with a piece of a copper rod.

I do have on hand some of those $0.99 eBay cheapie 18650 holders, but the wires that came soldered with them are incredibly thin, and the whole thing just looks poor in general, so I am feeling concerned that it might affect test results.

Click to expand...

I use these butI have soldered new wires in a new way....pass the new wire through the rivet hole of the - contact (spring), through the spring itself, and soldered it right at the tip of the spring.
Same goes for the + contact.
This way you have wire on battery contact only.....

look up 18650 holders on digikey

HKJ said:

For all my test I have used this type of holder:

Here is the improved version I have used the the 2012 battery test:

The important point is that I uses separate wires for current and measurement, but this is not possible on the CBA.

Click to expand...

Hi hkj, found this post through google images just wondering what is the third cable for...?

Nowadays there are off-the-shelf solutions, e.g. this 20A unit

fedcas said:

Hi hkj, found this post through google images just wondering what is the third cable for...?

Click to expand...

There is 3 sets of cables: Electronic load, electronic load sense and power supply. The power supply connection is routed through a relay so it is only connected when charging.
I do not use this type of battery holder anymore, all my test today are done with something similar to what Gauss163 shows.