Last year, Amber from Arizona made the financial case for rechargeable batteries. There’s no question your up-front investment in rechargeables will pay off quickly. However, deciding to invest in rechargeables is just the start. There are several different kinds on the market, and it’s useful to understand the differences. Each type has strengths and weaknesses, and not all chargers are created equal. Here’s a quick primer on what you need to know.


Nickel-Cadmium: Sometimes referred to as NiCd, or "nicad," they’re inexpensive and work with most chargers. However, they have many shortcomings. Their life per charge isn’t as good as newer technologies and they lose a lot of their charge just sitting on the shelf. Most importantly, if you don’t run the battery down completely each time, it will start to lose charging capacity. This is called the "memory effect," a major problem with NiCd batteries. Summary: A good general-purpose rechargeable with low purchase price. Use them in kids’ toys and electronic devices with moderate energy drain, wherever their shorter charge life won’t be an issue.

Nickel Metal Hydride: Abbreviated as NiMH, nickel metal hydride batteries are a substantial improvement. They last longer than NiCd and resist the memory effect, so you’ll continue to enjoy that extended charge life for a long time. They cost more than NiCds but the difference in charge life compensates handily for that. Summary: An excellent all-around battery for general purpose domestic use and high-drain devices as well.

Low Self-Discharge NiMH: An improved form of nickel-metal hydride battery first developed by Sanyo. They keep their charge much better in long-term storage, retaining up to 85 percent of it after a year. This means you can keep charged batteries on hand at all times and not be out of action while they’re on the charger. Summary: Higher purchase price than regular NiMH, but it sure is handy to have batteries always charged and ready to use.

Rechargeable Alkaline: Rechargeable alkaline batteries are different from other rechargeable batteries. They work just like a conventional alkaline battery, except you can recharge them. If you have electronics that tell you not to use rechargeables, good news! You can use these ones. Also, unlike NiCd and NiMH batteries, they last longer if they’re topped up regularly instead of running all the way down. They need a different charging system, though some advanced multi-purpose chargers will handle them. Once charged, you can store them much as you would with any other alkaline battery. Summary: Use them like any other alkaline battery. Best for toys or electronic devices with low to moderate drain, excellent shelf life once charged.


Standard charger: With NiCd or NiMH batteries, the slower the charge the longer your rechargeable batteries will last. A standard charger will perform a full charge on NiCd or NiMH batteries in 6 to 12 hours, depending on the capacity of the battery and the charger. This is slow enough to maintain a good lifespan for your batteries, while giving you next-day use.

Conditioning charger: A conditioning charger protects against memory effect by draining the battery fully before starting the charge portion of the cycle. This maintains the charge capacity of NiCd and NiMH batteries. It can also help restore lost capacity to a battery that’s developed memory. Every discharge cycle on the charger will restore a portion of the battery’s lost capacity.

Quick-charger: Quick chargers are for the impatient child in all of us. A well-made quick charger can charge up a pair of AA batteries in as little as 20 minutes, depending on the model. With two sets of batteries and a quick charger, you can keep the greediest of toys working continuously for hours on end. The downside is that quick charging will reduce the lifespan of the batteries.

Alkaline charger: Manufactured specifically for alkaline rechargeables. Don’t put NiCds in an alkaline charger or vice versa.

Charging pad: A flat "place mat" for your batteries and battery packs. The pad means you can charge non-standard batteries and battery packs if you lose the original charger. Read the instructions carefully, because pads won’t charge all types of batteries.

Capacity: Buy a charger that’s large enough for your family. Large models can charge a dozen AA batteries at a time, enough for even a multi-kid household.

So, where can you get your best deal on rechargeable batteries?

  • As always, watch your local retailers.
  • Check the major manufacturers’ websites and Facebook pages for deals.
  • Online, there are even more options. Here are two good ones: and
  • Don’t forget about Amazon. Not only do they have most major brands at competitive pricing, they always have extra ways to save including online coupons. You can also choose a battery and ask to be notified by e-mail when the price drops below a certain point, with their Subscribe & Save service.

This has been a guest post by Fred from New Brunswick, Canada
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