Testing C/D cells in Maha C9000

[scot]

Hey skinneysloth, have you done any breakin or discharges with the pictured cells? Just curious how good this setup works.

 

[Skinnysloth]

Hey skinneysloth, have you done any breakin or discharges with the pictured cells? Just curious how good this setup works.

Indeed I have. I've used it to break in two AccuEvolution LSD C and D cells.

With the C cells rated at 4500 mAh the break in capacities were:
1. 4704 mAh
2. 4776 mAh

D cells rated at 10000 mAh:
1. 9417 mAh
2. 9343 mAh

These results are in the same ball park as the OP's findings.

With a similar setup on my hobby charger (no dummy cells were needed), I was able to use a charge rate of 5A and discharge rate of 1.5A (probably the limit of the hobby charger) on the D cells. On the Maha c9000, it was able to handle the discharge rate of 1A on the D cells with no problem.

 

[dex138]

Hi Russel.
Nice clean setup you got there. Where did you source your materials?

I made this adapter a while back for performing break-in, and testing capacity, on D cells with a MH-C9000.

(I apologise for the poor angle. The display is a little hard to read.)

I made the charger end of the adapter from teflon with brass ends.

That way I could feed wire through the center of the teflon body, solder then to the brass ends, and thread the ends into the body.

 

[Russel]

I purchased the brass, steel, teflon, and copper from onlinemetals.com everything else is from material I had laying around.

I've updated the D cell holder. The contacts are copper with the negative contact protruding and the positive contact recessed.

 

[dex138]

OK, then from that I must conclude that you made all the components yourself, from the raw materials?

Heh, now thats what I call a sweet holder! Did you make one for 'C's too? hmmm......prolly not I'm guessing, this one looks like it could do both.

 

[Russel]

Yes, I machined the parts myself with a Sherline lathe and mill.

I only made this one battery holder for D sized cells, but it seems to hold C cells well enough also.

 

[Black Rose]

Nice work Russel :thumbsup:

 

[TakeTheActive]

Yes, I machined the parts myself with a Sherline lathe and mill...

:green: :bow: :goodjob: :santa:
(TTA being cryptic)

 

[ptewee]

has anyone tried doing this with 9v cells? apparently, i need to charge 9Vs more than Cs or Ds... :tired:

 

[daf3m]

has anyone tried doing this with 9v cells? apparently, i need to charge 9Vs more than Cs or Ds... :tired:

9volt batteries need 9 volt chargers..:candle:

 

[Black Rose]

9V cells could be done but because their capacity is so low (most are less than 200 mAh) and the lowest charge rate from the C9000 is 200 mA, you would be charging the cell at more than 1C.

 

[TakeTheActive]

9V cells could be done...

Well, kinda - if you OPEN up a 9VDC BATTERY to expose the connections to the individual 1.2VDC CELLS, you could attempt to charge it (@ 200mA minimum) as you stated.

For me, 9VDC rechargeables have always been a PITA since it always seemed that ONE CELL would die rendering the battery useless (since it either started at a 'handicapped' 8.4VDC or 7.2VDC anyway). Since my reading of the CPF 'Batteries Included' Archives, I've changed my 'strategy' a bit - instead of running the device until it stops working , I now keep a chart of 'When Installed' and try to recharge it earlier. I also pulled my old GE NiCD 12mA chargers out of retirement for my 2 Harbor Freight 100mAh NiCDs and 1 160mAh NiMH, going for the ~0.1C (or less) 'Self-Balancing' charge (compared to the 15mA Sears DieHard and the 23 mA RadioShack 23-428).

I recently lost 2 out of 5 DieHard 8.4VDC 150mAh NiMHs from 12/2000 with a "Green Crud" that ate through the negative terminal's rivet - something I don't recall seeing before. But, nonetheless, almost 10 years is a good run for a sealed battery. 1 out of 2 Varta 150mAh NiMHs from 01/2003 died over a year ago, which is disappointing - I was expecting better from Varta (which I thought was a good brand). That's another reason why I'm giving Harbor Freight a shot.

 

[Face]

I would love to have a setup like this for charging C and D cells with my C9000. I can't be the only one.

Would anyone be interested in producing a kit if there was enough interest from other members?

 

[Face]

I would love to have a setup like this for charging C and D cells with my C9000. I can't be the only one.

Would anyone be interested in producing a kit if there was enough interest from other members?

I guess not then. Shame as I would have thought something like this would have been a big boon to members of this forum.

 

[Black Rose]

I think most folks that want to do this just throw something together for themselves like I did with the wires and magnets.

I plan on rebuilding the one I made with actual battery holders to make it more plug and play.
I just need to get hold of some Delrin rods to make the fake batteries.

 

[samgab]

@ Russel ... Wow, that's impressive! I've just ordered a C9000, and ever since I've been mulling over ways to make it work with D cells... had a bit of a hunt around on this amazing forum and whaddayaknow! People who came before me have already done it, and way better than I could hope to.

 

[Russel]

There are a lot of ways to do it. Many people use the simple magnet method with a dummy AA cell. I went a little further, partly because I need to justify purchasing the Sherline mill and lathe that I have!

 

[CyberCT]

I purchased the brass, steel, teflon, and copper from onlinemetals.com everything else is from material I had laying around.

I've updated the D cell holder. The contacts are copper with the negative contact protruding and the positive contact recessed.

Russel, I'm very interested in doing a setup very similar to yours. I poked around at that metals site you mentioned but couldn't really find anythign familiar to what you used. If you have a minute could you maybe give me a link to each component on their site that you used for your setup? I'm probably going to end up buying those Accupower D LSD cells and I have a Maha MH-C9000 so I should be able to measure the mah values of them with the Maha. So I need to fabricate an adapter like waht you have

 

[jayflash]

Yes, I'm also impressed with the high quality of these adapters and unless the quality is high it probably won't work well. No half way solutions for this.

I'd be interested in obtaining such a nice accessory, but doubt anyone would be willing to make them for an affordable price. I'm sure a lot of time was put into these. Unless they were mass produced and would actually sell in large enough quantities, they'll remain a wish.

 

[CyberCT]

Just give me a link to all the parts and I will figure out how to fabricate some for myself.