New NiMH D cells 11,000 mAH now available

[ElectroCaver]

The New POWEREX MAXIMUM LIFE 11,000mAH NiMH D cells from MAHA ENERGY are now available from Thomas Distributing:
http://www.thomas-distributing.com/mh-2d110.htm

I love my MAHA Powerex 2200mAH AA's, so these new D's should be nothing short of awesome! I'm going to order some, but I'm looking for suggestions as to what charger to use to fill these electron tankers?!

 

[FalconFX]

Awesome! These'll kick the 9Ah batts down a little further...

 

[Catapult]

Whole wheat macaroni! /ubbthreads/images/graemlins/ooo.gif The same goes for the price.

 

[zmoz]

[ QUOTE ]
FalconFX said:
Awesome! These'll kick the 9Ah batts down a little further...

[/ QUOTE ]

 

[FalconFX]

And it's about time, too, I guess... Maha had been stuck at the 7500mah mark, which really prevented me from getting their Ds in the first place...

Kudos for the jump...

 

[eluminator]

How much bigger than a standard D cell are they? Do you need a hammer to get them in a flashlight?

I think the CCrane is the best charger. But it's really a kit cleverly disguised as a ready-to-use charger. When the coil springs break loose from their moorings, you have to open up the case and re-attach them. If you aren't up to the task, then I don't know. I guess the Rayovac PS3 isn't too bad.

If you have $80 bucks, you could try the new Saitek. I presume it works the same as the CCrane, but maybe they fixed the spring anchor problem.

 

[zmoz]

They should be the same size as a standard D battery. /ubbthreads/images/graemlins/wink.gif

 

[FalconFX]

I have a hex of new Mahas, and they are pretty much the exact same size as a regular D alkaline.

The one thing I do notice is that they are actually a tad bit heavier (by handheld sensation) than regular Duracell Ds... Quite interesting...

I did a straight runtime test on these guys with an Elektrolumens Starlux (early model), and I quite after about 4 straight days of output. It was in moon after all that time, but it wasn't losing any of that moon mode brightness anytime soon. I think 11Ah is a generous rating for these guys, as I really do believe it's got to be holding more charge than that...

 

[itsme1234]

Maybe CCrane and PS3 are good - but not for D's. Even with 10 years old 4000 mAh NiCads they are still overnight_and_most_of_the_next_day chargers. With the new NiMh they are more like "over the long weekend" chargers (keep in mind that the current from the specifications is severly overestimated, at least for the Rayovac).

[ QUOTE ]
eluminator said:

I think the CCrane is the best charger. But it's really a kit cleverly disguised as a ready-to-use charger. When the coil springs break loose from their moorings, you have to open up the case and re-attach them. If you aren't up to the task, then I don't know. I guess the Rayovac PS3 isn't too bad.


[/ QUOTE ]

 

[FalconFX]

This is why those 3-to-D and 4-to-D adaptors are so golden...

It takes 60-100 minutes to charge 4x 2.2Ah NiMH AAs, and it takes 12+ hours to charge an 11Ah D...

A parellel 8.8Ah NiMH D (4xAA NiMH 2.2Ah) being charged in 100 minutes is MUCH better than waiting 12+ hours for a 11Ah D...

Then again, 4x AA NiMHs will never be able to pack 11Ah of power...

 

[itsme1234]

I would be _so_ happy to charge D's with 1+ A (you need well above 1A to charge 11 Ah in 12h because you don't have 100% efficiency). Unfortunately most chargers charge only a couple hundreds mAmps so we are back to well over 24h.

[ QUOTE ]
FalconFX said:

It takes 60-100 minutes to charge 4x 2.2Ah NiMH AAs, and it takes 12+ hours to charge an 11Ah D...


[/ QUOTE ]

 

[FalconFX]

http://www.hobbiesr.com/dtx/dtx-chargers/dtxp4110.htm

There are chargers out there that can do much better than 4.5Amps, but the batteries would explode from this amount of charge current if it's not capable of handling it. That's why you see most manufacturers of chargers limiting their current to 800ma or below, to prevent over-heating of NiMH Ds. It's not that they can't increase the amperage. It's that it's literally unsafe to do so...

As amperage increase with Ds, we're stuck with the average consumer D-sized NiMH charger charging them for an entire day...

 

[zmoz]

[ QUOTE ]
FalconFX said:
Then again, 4x AA NiMHs will never be able to pack 11Ah of power...

[/ QUOTE ]

Just give 'em a few months /ubbthreads/images/graemlins/grin.gif

 

[star882]

"There are chargers out there that can do much better than 4.5Amps, but the batteries would explode from this amount of charge current if it's not capable of handling it. That's why you see most manufacturers of chargers limiting their current to 800ma or below, to prevent over-heating of NiMH Ds. It's not that they can't increase the amperage. It's that it's literally unsafe to do so... "
Why not add a thermal sensor?

 

[zmoz]

Shouldn't they be ok to 1C??

 

[FalconFX]

Why not add a thermal sensor?

What's the point of adding a thermal sensor, if the sensor's only job is to decrease current to the batteries to prevent overheating... Isn't that the point, to increase and deliver huge amps of continuous charging current to the batteries, to avoid and reduce the 24+hour charging cycle...?

To avoid something like thermal runaway in batteries, you have to keep current down, to somewhere like what we now see in "fast" chargers (like 450ma-800ma) for Ds, and that defeats the purpose of having something like a 4.5+Amp charger...

 

[Floating Spots]

[ QUOTE ]
zmoz said:
Shouldn't they be ok to 1C??

[/ QUOTE ]

Probably, but what happens when you stick an aaa in your charger?
Can it handle 11A?
What prevents someone putting the aa or aaa in this charger?

 

[zmoz]

[ QUOTE ]
Floating Spots said:
[ QUOTE ]
zmoz said:
Shouldn't they be ok to 1C??

[/ QUOTE ]

Probably, but what happens when you stick an aaa in your charger?
Can it handle 11A?
What prevents someone putting the aa or aaa in this charger?

[/ QUOTE ]

A flashlight/battery all in one! /ubbthreads/images/graemlins/wink.gif Well...couldn't there be a dedicated D charger, or just a dedicated spot in the charger for D batteries? They are longer than AAs.

 

[wualta]

These Ds sound great, but for the life of me (which is not very much), I can't find a Maha charger on the Thomas site that will handle this big dog. We don't want to charge for 24 hours-- charging's not efficient at that rate. Surely (you don't mind if I call you Surely?) Maha makes a charger to go with their own D cells!

Walt Brand

 

[itsme1234]

There are a couple of things to prevent you from using AAA with the D charger:

a. the same things that prevents the people from sticking spray cans in fire: big bold warnings

b. laws of physics: AAA are smaller than D's and air is not a good conductor

c. I thik it's called Pavlov conditioning: do it once, kaboom. You won't do this again.

[ QUOTE ]

Probably, but what happens when you stick an aaa in your charger?
Can it handle 11A?
What prevents someone putting the aa or aaa in this charger?

[/ QUOTE ]