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Rechargeable batteries, from Li-Ion to NiMH to Ni-Cad

January 1, 2004

in All Articles,Miscellaneous

Today’s electronics consume batteries the same way I consume pizza: With gusto. And with Christmas approaching, you’d better be prepared. Even if you don’t intend to buy remote-controlled cars and “See-Me-Smirk Susie” for everyone in your family, chances are you have many devices using many batteries.

You’ll often see ads for rechargeable batteries, claiming hundreds of dollars in savings by recharging. This might sound too good to be true, but it’s not. You really will save lots of money with rechargeables. But like most everything in life, that’s not the whole story. A rechargeable battery cycle doesn’t last as long as a non-rechargeable battery. Rechargeables don’t work well in cold weather. If not charged, a rechargeable battery will lose its energy within a few months. But used properly, rechargeable batteries will indeed work well and save you money.

Battery Types

Rechargeable batteries are made of metals that can charge, store and release electricity. Some metals do this better than others. When shopping for rechargeable batteries, you’ll probably see these types:

  1. NiMH: (Nickel Metal Hydride): Purchase these for smaller devices like handheld CD and MP3 players, toys and cameras. Ni-MH batteries give you the best bang for your buck, and are eco-friendly so you can dispose of them normally. You can recharge these 500-1000 times.
  2. Li-Ion: (Lithium-Ion): This is the best performing rechargeable battery type, but is very expensive. Best for equipment requiring constant use or frequent recharges, like laptop computers and cellphones. You can recharge these 500-1000 times.
  3. Ni-Cad (Nickel-Cadmium) or Rechargeable Alkaline: These are still pretty popular, but stay away. These have many drawbacks including poor capacity. You can recharge these 50-500 times.

Battery Capacity

Rechargeables have a rating called mAh (milliamp hours). The higher the number, the longer the batteries will last before needing a charge. Currently, the highest ratings out there are near 3000 mAh. Online purchasing is usually the best, as local retailers won’t always label the mAh rating or have the best batteries in stock.

The Charger

  1. Get a “smart charger”. These should charge batteries quickly and allow you to leave the batteries in the charger until you’re ready to use them.
  2. Make sure the charger is rated for the batteries you’ve purchased. If you have a NiMH charger, only charge NiMH batteries. (Never attempt to recharge non–rechargeable batteries.)

As technology has improved, batteries haven’t kept pace. Today’s power-hungry devices are only measured in hours of runtime. It’s pretty sad when you compare the incredible rate at which technology is advancing with the comparatively small improvements in battery capacity. So what can we learn from this article, besides the fact that I like to use the word “rechargeable”? Until science comes up with a way to give us truly long battery life, our solution is to look away from the single-use batteries and start wasting electricity more intelligently.

The website for all your rechargeable needs:

AA and AAA rechargeable batteries:


Recommended AA and AAA battery charger:

Readers Respond

Ann writes in with some excellent advice:

“I just want you to know that I read your column about the rechargeable batteries. I have all 3 of my boyz on rechargeables for their GameBoys and have not paid for regular batteries for about 3 years. It is the MOST wonderful way to cut out the expense of batteries. Also, they each have their names on their own batteries so it cuts down on ‘Who stole my batteries?’ They are very good about keeping them charged and keeping them away from the other brothers because they all know there are no batteries to just dig into anywhere in the house. We are HUGE fans of these batteries.”

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