NiMH C cells, at least, are available. Not sure about Ds.

I've got a few NiMH D cells. They take a long time to charge fully. The good news is that unless you use them a lot, you only need to top them up. I have a 3xD lantern and a 3xD Maglite, and I have no idea how long the batteries actually last because they've never died prior to a maintenance charge.

Hi Russ,

Are they low discharge D cells? Would you recommend the manufacturer and what charger you're using?

Thanks

I got them on Amazon:
Odec D Cell Rechargeable Battery, 2-Pack 10000mAh Deep Cycle NiMH Battery
and,
Tenergy D Size 10,000mAh High Capacity High Rate NiMH Rechargeable Batteries

Of the two, the Odec are lower self-discharge and will eventually replace the Tenergy's. The primary reason to get them was to save Maglites from alkaline batteries.

I'm using a Tenergy charger which has four independent bays which can accommodate AAA-D cells. I'm sure there are better chargers but it's what I bought a few years back. Looking at the specs of the T-9688 Super Universal LCD Battery Charger and Tenergy Advanced Universal Charger TN190 , they're only spec'd up to 9000mAh for D cells. That may be why mine never finishes charging the D cells. The Maha PowerEx MH-C808M Charger is rated for 11,000 mAh.

Thanks Russ!