There are now a number of low-discharge D-size cells available. These cells are as powerful alkaline batteries, and they hold 85% of their charge for a year. The highest-capacity D-size rechargeable cells are rated at 11000-12000 mAh (milliamp hours).
Here are our recommendations:
The Highest Capacity D-Size Batteries: Powerex
The Most Affordable D-Size Batteries: Tenergy
Tenergy makes D-sized rechargeables which are rated at 10,000 mAh (milliamp hours). These batteries are about half the price of the Powerex batteries, but they offer a capacity of 10,000 mAh (milliamp hours). They are priced at about $25 for a pack of four cells. These batteries have the same low-discharge chemistry, and will hold most of their charge for a year.
The Worst D-Size Rechargeable Batteries
I don’t recommend getting Energizer D-Size rechargeables, because they are AA cells that have been repackaged in a D-sized shell!
The Best D-Size Battery Chargers
See our post The Best Chargers For C And D Sized Batteries.