I seldom touch this size of NI-MH battery, so I don’t know much about it
What is the general charging current and the fast charging current of the power battery? 
Thanks
For an 8000-10,000 mAh D, I’d say 2-3A.
Chris
I have a bunch of D’s. I generally use 2A.
Also, you need to make sure first by checking the capacity. Lot of cheap “D cell” NiMH cells are actually just an AA stuck in a hollow shell.
Thanks
thanks
2A is all my charger will output. But theoretically a 10,000 mAh D cell could take a charge at “1C”, which in this case is 10A.
Like other batteries with overblown capacity claims, I’ve never seen a ‘real’ 10K D-cell, though I have a number that have such nonsense printed on them. They seem to max out about 8K.
Torchy tested a bunch. Capacities, and claimed capacity, were all over the place. Many were pathetic. A couple did break 9K. I contend they would not have held that capacity long.
My main charger (Maha 808) that takes multiple D-cells maxes out at 2A, so that’s what gets used. It works fine.
I have tried higher with hobby chargers but that’s not set up for anything but a single cell. Not sure I’d go over 5A, even on a high cap cell, due to the mass and heating.
My Powerex MH-C9000 charger can only do 2A max so that’s all I charge them at (with adaptors). Like flydiver above, I think I would try them at 0.5C (~4A) if my charger could do it but it doesn’t bother me - a slower charge is fine.
What is the best D battery on the market?
cool，li-ion 32700， 32650 battery ，6-12A charge current is ok
From what I've read, they're all terrible, especially in the long run.
It's better to use eneloop AA batteries with something like this:
Can’t help there with the ‘best’ D. I’ve had a number but at this point they are all getting pretty old, and my primary use for them, scuba lights, is no longer needed. Best I can do is point you at the Torchy test.
I CAN tell you the EBL D’s, which I got in a recent package buy, are no where near their claimed capacity.
It take a long time (years) to test longevity, so that’s a difficult parameter to get data on.
Tenergy premiums (model 10105) are probably ok. I haven’t tested them, nor have I seen any tests of them. They are not low self discharge, but the manufacturer’s datasheet of similar models (10103 and 10100) shows >80% charge retention after 6 months at 25C, > 65% after 1 year at 25C. The 10105 datasheet doesn’t have this section included. This self discharge rate seems acceptable to me. The 10103 has solder tabs and is specified as having a minimum capacity of 9500 mAh, the 10105 and 10100 datasheet’s state a minimum of 9000 mAh.