Just bought a quantity of 2 (16 total batteries). First I went online and found the Tenergy data sheet of the batteries. They are supposed to have 65% or more charge remaining after one year, stored at 20C. That's LSD enough for me. Ever six months I do the "conditioning mode" for my LSD AA and AAA batteries anyway. That is an insane price!
Best rechargeable "D" cell
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357mag1
Enlightened
I bought 16 of them too and have been performing discharge tests as a way of cycling the batteries. They seem to be averaging between 7500 - 8100mah. They might improve some but I'm pretty happy with these cells. They rival the Tenergy Premiums for maintaining voltage under a load.
Capacity doesn't hardly seem affected whether discharging at 2amps, 3amps or 5amps.
I recently let some Premium cells sit for just over 6 weeks. The static voltage measured right around 1.3v which was the lowest of the cells I tested (all others were LSD). The Premiums had only lost about 100mah each from freshly charged tests, about the same as the LSD cells. Best part was they easily beat all other cells in maintaining a higher voltage under load even the Centuras (second best).
Hopefully these cells perform in a similiar manner.
I have some setting charged on the shelf at the moment and will test them in 6 weeks or so.
Capacity doesn't hardly seem affected whether discharging at 2amps, 3amps or 5amps.
I recently let some Premium cells sit for just over 6 weeks. The static voltage measured right around 1.3v which was the lowest of the cells I tested (all others were LSD). The Premiums had only lost about 100mah each from freshly charged tests, about the same as the LSD cells. Best part was they easily beat all other cells in maintaining a higher voltage under load even the Centuras (second best).
Hopefully these cells perform in a similiar manner.
I have some setting charged on the shelf at the moment and will test them in 6 weeks or so.
Thanks for doing all these tests 357mag1. So the ones that I (and you) just bought are actually just an 8,000 mah battery or less on average? I was expecting more. The Tenergy data sheet says min capacity is 9000 mah. You mentioned though that under load they rival the Tenergy Premiums. Under what load specifically? I will now be purchasing the Fenix TK70. So that will be the "load" that all four of these batteries (in a series) will experience. Which is quite a lot I think. Do you have any tests of the capacites under a load like that?
Using a Triton 2 EQ charger at 3a dischage I found these to be in between 8000-9000mah, when they charge they are about the same.. I have just finished a direct drive SST-90 mag 3d and these are able to provide 10.2-10.5a without any trouble...(using a clamp meter, measurement taken just before the led)
I have purchased at least 32 of these, 16 of which have made it here and are working just fine, the other 16 are in the mail...
Yes it is.. these are about 10 bucks each from the normal suppliers..
I have bought from this guy before, he is a liquidator, so once these are gone he wont get anymore.. (at least previous experiences with him anyways)
357mag1
Enlightened
So far the highest I've seen is 8100mah and I'm using a Triton 2 EQ as well. My batteries arrived with static voltage readings around .9V and some batteries had less than 7000mah capacity on the first cycle. They have all climbed above 7500mah after a couple of cycles (not gentle ones either). With proper cycling they may continue to improve.
The highest discharge rate I can do is 5amps (Not on the Triton). I've only done a couple of the Premiums and these Standard (Blue) batteries at that rate and so far the Standard batteries seem to be holding right with the Premiums.
Tailcap current with 4 Premium D cells is right at 6.4amps in my TK70s so you should get over an hour of runtime.
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I am interested in the AA adapters to substitute for D cells in several 2D Maglights with Malkoff Dropin. The adapters you spoke of are 2AA in each adapter or 1AA. Also, are you pleased with the result using the adapters. Thanks a bunch.
The Tenergy datasheet says to charge their D cell at 1 amp for 16 hours. Isn't that the "soft charge" mode of the Maha MH-C808M charge at 1 amp? And the regular charge at 2 amp? I thought I read somewhere else on this forum (maybe the TK70 thread) that someone said to use the 2 amp charge for D cells, not the 1 amp charge. ANy thoughts?
A general rule of thumb is to charge any NiMH at 0.5C, in this case that is a 5a rate. I know that they will need cycling (normally) before reaching max capacity (at least when they have been sitting for so long) I wonder if the 1a for 16hrs was the initial charge and then you could go to the 0.5C charge.. I have read somewhere these cells can handle up to 8.0a charge rate...
Russel
Enlightened
I've noticed a couple 10,000mAh NiMH D cell manufactures recommend about 1A for 16 hours as the standard charge rate, and 2A for 7 hours for fast charging. Tenergy recommend 950mA for 16 hours as standard and 1.9A for 7 hours as fast charge. I would be reluctant to charge those cells at 5A. I'm thinking that because of the relatively small surface area with respect to the capacity of these NiMH D cells they can't dissipate heat as well as AA or AAA cells and the 0.5C charge rate may be too high.
i bought 12 of them, might buy another 8 of them though.
So it is perfectly fine to charge these D cells in the Maha MH-C808M at the standard rate (2,000 mah) instead of the "soft" mode (1,000 mah)?
I'm thinking of maybe doing two "conditioning" modes per D cell battery in the MH-C808M (to break them in) and then doing a discharge test on my MH-C9000 with modified adapters to charge D-cells. I'm not sure what the maximum discharge rate is for the C9000. That should tell me the capacity of each cell, correct?
I'm thinking of maybe doing two "conditioning" modes per D cell battery in the MH-C808M (to break them in) and then doing a discharge test on my MH-C9000 with modified adapters to charge D-cells. I'm not sure what the maximum discharge rate is for the C9000. That should tell me the capacity of each cell, correct?
hank
Flashlight Enthusiast
I'm puzzled looking Tenergy's products page:
http://www.tenergy.com/Site/D-NiMH are their button top consumer cells.
Are the blue button top 10,000mah D cells with the big lower case "e" on them an older design, or am I missing something?
http://www.tenergy.com/Site/D-NiMH are their button top consumer cells.
Are the blue button top 10,000mah D cells with the big lower case "e" on them an older design, or am I missing something?
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bruintennis
Newly Enlightened
Great thread. I was wondering about D cells too.
357mag1
Enlightened
Unless i needed them in a hurry I would charge at the slower rate. The faster you charge a cell the more likely you are to shorten the life span.
I would definitely condition them at least once and twice would probably be better if you have the time.
The C9000 has a max discharge rate of 1amp and yes it should give you the capacity.
357mag1
Enlightened
Yest the Blue cells are the older design. They appear to still be available on all-battery.com but at pretty much the same price I would get the Premiums.
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For the C808M, should I do the "conditioning mode" with the "soft" mode? Apparently you can do both with this charger? That supposedly takes waaayy too long from what I've read for D cells. Since the capacity is much higher on D cells does it really matter if I just do it in normal mode?
Also, doing two "conditioning mode" cycles for each battery won't be harmful to the battery, will it?
Does the 808M cycle when I insert a battery (charge if needed, then discharge, charge) or does it just charge until the battery is fully charged? I want to do some cycling.
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Tenergy seems to be discontinuing these D cells. The ebay link in this thread has a great deal on them.
357mag1
Enlightened
I don't have an C808M yet (I should in a few more days) so have no experience to answer questions relating to that unit.
Best for batteries when conditioning to use a slow charge and discharge. 2000mah AAs take over 30 hours on the C9000 if I remember correctly.
If you are gettiing 16 cells mark each cell and charge them all. Throw 12 of them, 4 at a time in the TK70 and play around with it for 15 minutes with each set. Charge those twelve up again and start the slow conditioning cycle on the other 4. That should keep you in power until they complete. Then repeat the process until you have conditioned them all.
hank
Flashlight Enthusiast
uh, oh: an earlier CPF thread:
http://www.candlepowerforums.com/vb...ed!-What-Now&p=3561799&viewfull=1#post3561799
"Maha MH-C808M Charger Melted! What Now??
When I was researching this charger, I found two reviews about it catching on fire..."
One of them with Tenergy 10,000 NiMH D cells.
Of course there's always going to be one or two problems out of tens of thousands.
http://www.candlepowerforums.com/vb...ed!-What-Now&p=3561799&viewfull=1#post3561799
"Maha MH-C808M Charger Melted! What Now??
When I was researching this charger, I found two reviews about it catching on fire..."
One of them with Tenergy 10,000 NiMH D cells.
Of course there's always going to be one or two problems out of tens of thousands.
