Test Results for Accupower Evolution C Size Low Self Discharge Cells

[Power Me Up]

I've completed testing on a total of 10 of these cells purchased from Thomas Distributing:

http://thomasdistributing.com/shop/...batteriesbrprecharged-2-battery-pk-p-998.html

All discharge tests were done on my 0FAB02 firmware Maha C9000 charger/analyzer.

Out of the packet, the cells gave an average of:
4010mAh
(Min 3862, Max 4348, St Dev 128)

After charging on the C9000 or charged with a C808M and topped off with the C9000, they gave an average of:
4913mAh
(Min 4865, Max 4986, St Dev 38)

Charged only on the C808M, they gave an average of:
4670mAh
(Min 4552, Max 4730, St Dev 57)

I'm quite impressed with the performance of these cells - when charged with the C9000 they performed 9% better than their labelled capacity. Even when charged on the C808M, they averaged nearly 4% better than specified despite the lower charge completeness of the C808M!

Unfortunately, there were no markings on the cells to indicate when they were manufactured (and it's impossible to know how fully charged they were when new) so it's not possible at this stage to evaluate their self discharge rate, but at 89% of rated capacity out of the package, they can definitely claim that they're pre-charged and ready to use!

Now to find some time to test the D sized versions of these cells!

Edit: Test results for the D sized cells can be found in this post:
http://www.candlepowerforums.com/vb/showthread.php?t=189208

Edit2: I've created a new thread with a photo of how I've attached the C & D cells in the C9000:
http://www.candlepowerforums.com/vb/showthread.php?t=213363

 

[mdocod]

AWESOME results! the consistency from cell to cell when charged by the C9000 is amazing, within 2.5% of each other. IMO these could be used in pack applications pretty well... thank you for taking the time to report some results on these!

 

[NA8]

 

[Mr Happy]

How did you connect them to the C9000? Home-made adapter?

 

[monkeyboy]

These are impressive results and not far off the regular "6000mAh" Accupower cells tested by silverfox. Any idea how these perform under loads?

 

[Power Me Up]

How did you connect them to the C9000? Home-made adapter?

I used individual holders for each cell and AAA to AA adapters from DealExtreme to hold the leads against the terminals of the C9000.

The adapters from DealExtreme can be found here:
http://www.dealextreme.com/details.dx/sku.3657

Unfortunately, it ended up being a little more tricky than I expected to get the negative leads to hold just right, but once I got them in they've been pretty solid.

 

[Power Me Up]

These are impressive results and not far off the regular "6000mAh" Accupower cells tested by silverfox. Any idea how these perform under loads?

Sorry, no - the maximum discharge rate on the C9000 is 1A and it doesn't provide any means to graph the terminal voltage during the discharge.

If Silverfox or someone else with a CBAII or something similar did some discharge curves on these cells I think it'd be rather interesting.

 

[Gene]

Man, I've been waiting for these for a long time! Does anyone know if my Vanson Speedy Box will charge these okay?

 

[thekobk]

If you want to ship a couple of these to me I will run any test you want and I would pay to ship them back. Any thing to help out CPF. If I owned a device that needed some C sized cell I would buy them and run them through my cba II for you but unfortunately I don't. Sorry.

 

[Turbo DV8]

These are impressive results and not far off the regular "6000mAh" Accupower cells tested by silverfox.

Link to that test? Thanks.

 

[Power Me Up]

3 Month Self Discharge Test Results

Discharge capacities on 4 of these cells came to an average of 4108 mAh after 3 months of self discharge. Minimum capacity was 4040 mAh and max was 4199 mAh.

Compared to the initial capacity results for the same cells charged on the C808M, their average capacity was down to 87.9% of their original average capacity (4676 mAh)

To be honest, the results aren't quite as good as I was expecting, but they're still pretty decent IMHO.

It'll be interesting to see how the D cell results turn out...

 

[Supernam]

12% loss over a 3 month span doesn't sound too bad. It's not Eneloop status, but then again these cells are only about 20% less capacity than their non-lsd counterparts whereas eneloops are around 35% less than their non-lsd high capacity counterparts.

 

[Bimmerboy]

Re: 3 Month Self Discharge Test Results

To be honest, the results aren't quite as good as I was expecting, but they're still pretty decent IMHO.

Similar impression. They could potentially be worth the bucks. 3 of 'em in a P7 mod that only has to be topped up at 3 - 4 month intervals instead of every 1 - 2... good stuff.

It'll be interesting to see how the D cell results turn out...

Been waiting to see about those too. Good work, man!

 

[Anders]

Hello Power Me Up.

Thankyou for the results, good work,

Not bad results.

Anders

 

[SilverFox]

Hello Power Me Up,

Thank you for the test results.

I suppose the next step would be to see what the self discharge rate is for normal NiMh D cells. My initial "guess" would be that they would be down to around 60% of their initial capacity in three months.

Tom

 

[etc]

Thanks for the report.

Turns out C and D Accupower LSD have identical self-discharge rates.

 

[ElectronGuru]

on sale now
http://www.cpfmarketplace.com/mp/showthread.php?t=179694

 

[etc]

12% loss over a 3 month span doesn't sound too bad. It's not Eneloop status, but then again these cells are only about 20% less capacity than their non-lsd counterparts whereas eneloops are around 35% less than their non-lsd high capacity counterparts.

T

This test means that the 2% self-discharge rate as stated on the cells is a bit optimistic as it turns out.

 

[FredM]

All of the capacities were tested at a 1A draw?

Thanks

 

[Power Me Up]

Pretty much - there were a couple of discharges that I did at 900mA, but the difference would have been negligible...