+1, will they do 5 amps+ like eneloops?
I almost went and ordered some, but Heck, with the shipping charge, it's cheaper to go to Amazon and buy eneloops with Prime.
They are probably getting hot because of how fast you are charging them. Is that the slowest charge setting that charger has? I always heard it was bad for batteries to chqrge them fast, I charge mine at 200mah and have never had any of my batteries get warm. I use a La Crosse BC-700.
I think I still have a few of these cells banging around in a drawer somewhere. I’ll try giving ’em a 5A discharge test when I get home, that is if you guys don’t mind my terrible testing setup.
On this charger the discharge rate is always 1/2 the charge rate and I wanted the discharge test done at 500mA.
-Garry
Default Username wrote:
I think I still have a few of these cells banging around in a drawer somewhere. I’ll try giving ‘em a 5A discharge test when I get home, that is if you guys don’t mind my terrible testing setup.
That is very kind of you to offer. I certainly don't mind. It should provide at least a rough idea. We're talking about the AAA's?
I was thinking about the AA’s to tell you the truth. I’ve got some AAA’s as well, but I haven’t gotten around to wiring a battery cradle for them.
Here’s the test I promised. Cells are Turnigy 2400mAh AA’s purchased on April 15/2013. Charger is an old Duratrax Intellipeak Ice, and the DMM is a cheapo uncalibrated Centech P35017.
Cells have 10 cycles on them at most, and have been in storage for about 4 months now. All I did to this particular cell before the discharge test is top it up on my charger and let it rest for about 10 minutes.
Here’s the setup. The positive DMM lead is directly touching the cell top, bottom is touching the cradle spring. Cell is fully charged and has rested about 10 minutes in this photo.
Starting 5A discharge
(apologies for the irregular sample points)
—5 minute marks are in bold—
3 seconds — 1.212v — 3mAh
01:00 — 1.139V — 83mAh
03:20 — 1.082V — 272mAh
05:00 — 1.069V — 411mAh
06:01 — 1.063V — 496mAh
08:24 — 1.042V — 696mAh
08:40 — 1.039V — 717mAh
10:00 — 1.026V — 829mAh
13:12 — 1.000V — 1093mAh ————- battery reaches 1.0V mark on DMM.
15:00 — 0.995V — 1246mAh
20:01 — 0.967V — 1664mAh
23:57 — 0.916V — 1992mAh ————- battery voltage starts plummeting like a rock
24:21 — 0.906V — 2026mAh
25:00 — 0.888V — 2080mAh
25:24 — 0.873V — 2113mAh
25:40 — 0.857V — 2135mAh
26:00 — 0.836V — 2162mAh
26:22 — 0.798V — 2194mAh
26:31 — 0.774V — 2206mAh
26:37 — 0.753V — 2215mAh
26:42 — 0.735V — 2222mAh
26:48 — 0.711V — 2230mAh ————- charger terminates
Discharged battery at rest
I’ve got some white-top duraloops that I can toss into the mix tomorrow (no eneloops unfortunately). I’ll also look into testing the Turnigy AAA’s at 5 amps to see how they fare.
And in case anyone is interested, here’s a link to the photos.
http://www.flickr.com/photos/114747797@N03/
Thank you Default Username. I'm no expert, but that looks like a well executed home test to me. Looking at your second picture, it appears to say current is 4.57amps (at start of test). But when I recalculate it appears that the cell delivered an honest 5 amps the whole test:
| Elapsed Time | 5 Amp Theoretical | Actual/ Theoretical |
| 3 | 4 | 192% |
| 60 | 83 | 100% |
| 200 | 278 | 98% |
| 300 | 417 | 99% |
| 361 | 501 | 99% |
| 504 | 700 | 99% |
| 520 | 722 | 99% |
| 600 | 833 | 99% |
| 792 | 1,100 | 99% |
| 900 | 1,250 | 100% |
| 1201 | 1,668 | 100% |
| 1437 | 1,996 | 100% |
| 1461 | 2,029 | 100% |
| 1500 | 2,083 | 100% |
| 1524 | 2,117 | 100% |
| 1540 | 2,139 | 100% |
| 1560 | 2,167 | 100% |
| 1582 | 2,197 | 100% |
| 1591 | 2,210 | 100% |
| 1597 | 2,218 | 100% |
| 1602 | 2,225 | 100% |
| 1608 | 2,233 | 100% |
Do you think it was just because the test was just starting? Maybe I am calculating incorrectly.
@ ImA4Wheelr
Nice catch! Yes, my hobby charger takes a couple of seconds to ramp up to the set discharge rate. I probably should have used the 3 second shot for a more honest start discharge voltage (though upon looking at the pictures, it’s still reading at 4.98A as opposed to 5A).
Thank you again Default Username. Figured it was that, but I wanted to be certain I wasn't misinterpreting your data. I like your IntelliPeak unit. My Accucel can only discharge up to 1A. Is 5A the max on yours?
Technically it’ll do a 10A discharge, but if you try doing that with anything more than a 3S lipo pack it gets toasty in a real hurry J)