August 30th, 2013

Your Green Battery Guide – Rechargeables vs. Alkaline – The Great Battery Debate

Battery comparison chartTo recharge or not to recharge? Is it cheaper? When does it make sense to use regular batteries? In this blog, we will explore some current thinking around the issue.
First, the options. The Energizer Recharge systems available at London Drugs offer several battery models, sizes and charger configurations, depending on the devices you want to run. From the basic mini charger for 2 AA or AAA batteries, to the 4-battery Smart Charger that shuts off automatically to save power, and lets you know if one of your batteries goes bad.
According to the website, they offer 2 versions of rechargeables: The Recharge Universal, for devices that require frequent charging, and the Recharge Power Plus, designed for power hungry devices such as digital cameras.

Comparing single-use alkaline batteries to rechargeables

We compared the best battery deal energizer offers at London Drugs – 24 Alkaline batteries for just $17.99 – that’s about 75¢ each.
Regular price for 4 Recharge AA’s and the premium Smart Charger is $39.99. So in the worst case scenario, if you only bought those 4 batteries and used that one charger for them, the price per battery is about 10 bucks. (Realistically, the cost of the charger would be amortized over the lifespan of several battery sets)
Even with this biased comparison, the rechargeable batteries come even with the single-use batteries after being used just 13.3 times. To be practical, however, rechargeables (in my experience at least) lose some of their power over time, compared to alkalines. So a closer estimate might be 15 – 20 charges.
One blogger at calculated his family’s battery consumption yearly and compared it to investing in rechargeable systems. They were paying $77.70 a year for quality AA’s. The equivalent number of rechargeables and charger cost them $148.74 to set up. So after 2 years, they were basically getting battery use for free. (An interesting sidebar – a year’s worth of electricity to recharge the batteries came to a whopping 24¢!)
Now, let’s look at the waste. One set of rechargeables and a charger vs. 15 – 20 alkaline batteries. Of course, both can be recycled (right here at London Drugs) but that’s still 15 – 20x the shipping, handling and recycling energy use right there.

Single-use batteries still have their uses

So, it makes total green sense to use rechargeable batteries, but there are times when single-use alkaline batteries may actually be more practical.
According to some online sources, it makes more sense to use traditional alkaline batteries for low-draw devices like your clocks, radios, smoke detectors, programmable thermostats, and remote controls because they lose power at a much slower rate than rechargeables. And because traditional alkaline batteries can hold a charge for years when not in use, they are a better choice for items that sit unused for long periods, like back-up batteries and emergency flashlights. Here are a few tips for getting every electron of power out of your single-use batteries.

Rechargeable Battery Care and Maintenance

Many rechargeable battery problems are due to overcharging or improper storage.  Overcharging is usually caused by  poorly designed first generation battery chargers that continue to deliver current to batteries even after they are fully charged.  “5- hour” and “8-hour” timer type chargers can damage NiCd or NiMH batteries if they are frequently used to charge batteries that are only partially discharged.
Another common cause of damage to NiCd and NiMH batteries is leaving them in a device like a flashlight left “ON” after the battery has run down. Appliances normally switch off when the battery is discharged.  But some devices, like flashlights and many toys, will continue to drain the battery even after the it is run down.  Eventually this could cause the polarity of the battery to reverse.  Once this happens the battery will not take a charge. Rechargeable batteries should be removed from any such devices that will not be used for several weeks or longer.

Rechargeable batteries also are not without their challenges. Energizer claims they can be charged ‘100’s of times’, but that may be a bit optimistic, depending on how they are used. But as our calculations show, even if rechargeables are used only 20 times, you (and the environment) still come out ahead.

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