The 9 Best D Batteries
Editor's Notes
December 27, 2020:
Though it may seem all batteries are the same, this is actually untrue. They have different chemical makeups and capacities. For example, the Tenergy 90111 boast a 10,000 mAH capacity and a nickel-metal hydride construction, which doesn't suffer from the memory effect issue of nickel cadmium batteries. The Energizer NH50BP are also a rechargeable nickel-metal hydride option, however they have a much lower 2,500 mAH capacity, which means they require more frequent charging and aren't as well suited to high-drain devices. That being said, they are made from four percent recycled batteries, so you get a somewhat eco-friendly option for this trade off. There is often less differentiation in the capacities of single-use alkaline models, however they still doesn't mean they are all the same. Both Duracell CopperTop and Energizer Max are known for having a very long shelf life and little chance of leakage, whereas the AmazonBasics LR20 are more affordable, though have half the shelf life and a less robust construction than the former two.
November 04, 2019:
Originally introduced in 1898, frequently referred to as D cells and given the classification R20 by the International Electrotechnical Commission, D batteries are dry-cell, barrel-shaped devices with their positive and negative poles located on opposite ends (the smooth side is negative). They typically have a rated voltage in the neighborhood of 1.2 volts to 1.5 volts and tend to be reserved for medium- to large-sized equipment with high current-drain ratings (their bulky size is prohibitive when it comes to use in smaller consumer electronics). Places you might have seen them include your adolescent boombox and that monstrous flashlight you keep stored in your earthquake kit.
In a category so congested by options with significant similarities, price might seem like an obvious primary consideration, but there are a few other things that you should keep an eye out for:
Rechargeable vs Disposable: The two major selling propositions for disposable batteries are cost – their price per unit is more affordable, and convenience – remembering to charge batteries and waiting for them to finish charging are both avoidable pains. However, with rechargeable options like the Bonai High Capacity and the Tenergy 90111 boasting lifespans of 1,000+ charge cycles, it's easy to see how much fiscal sense rechargeable batteries make in the long run. They might cost you three to five times more than disposable alternatives, but nothing close to 1,000 times. In fact, most rechargeable batteries should pay for themselves within the first one percent of their life.
If you are going to go with rechargeable, favor nickel-metal hydride options over nickel-cadmium alternatives, as they tend not to contain harmful chemicals and don't suffer from the dreaded "memory effect" that plagues nickel-cadmium options – causing them to lose some of their capacity every time they're put on a charger before they're fully drained.
Environmental Impact: Besides theoretically keeping some 999 batteries out of a landfill every time you opt for a rechargeable battery over a disposable, there is a couple more ways to think green while shopping this category. Firstly, look for batteries that are built without the use of dangerous elements such as cadmium, lead and mercury. It shouldn't be tough; most top companies have taken steps in this direction already. Secondly, look for devices that come in fully-recyclable packaging, such as the AmazonBasics LR20 and the Duracell CopperTop.
Extras: Though hardly a deal maker or breaker, the molded storage cases that come with the EBL 906-4D are a nice touch, and help give you a bit of peace of mind if you're concerned about damaged batteries leaking in your luggage, for example. Another checkmark in the yes column for the EBL 906-4D is the fact that it comes with a battery charger, while other choices like the Bonai High Capacity require that a charger be purchased separately – at additional cost.