» Lenmar Battery, CHARGEABLES, AA, 4 Pack, 1.5V 1500mAh ALKALINE

Lenmar Battery, CHARGEABLES, AA, 4 Pack, 1.5V 1500mAh ALKALINE Reviews

Customer Rating:
Summary: Rechargeable Alkaline comes back from the dead?
Comment: First thing first: The Lenmar CHARGEABLES are Rechargeable Alkaline Manganese (RAM) cells, so they cannot be recharged using an ordinary NiMH charger. You need a charger specially designed for rechargeable alkaline cells, or one like the Rayovac Universal Battery Charger which can handle both NiMH and RAM cells.

As far as I can tell, those Lenmar "CHARGEABLES" are reincarnations of the Rayovac "Renewal" rechargeable alkaline cells. Rayovac marketed the Renewal batteries and charger system about 10-15 years ago. But due to various limitations (as explained later) it turned out a big failure, and Rayovac consequentially discontinued the whole Renewal product line.

At first glance, the concept of rechargeable alkaline cell sounds great, since it combines advantages from both ordinary alkaline cell (long shelf life, 1.5V terminal voltage) and rechargeable cell (multi-use). Unfortunately, it also inherited the biggest limitation of alkaline cell: high internal resistance. This makes it very inefficient when used in high-drain appliances such as digital camera or flash light. So it is only suitable for low-drain appliances such as wireless mouse, remote control, or smoke detector.

Another serious limitation is energy density. A new Lenmar CHARGEABLES AA cell starts out with 1500mAh, which is only half the capacity of a single-use alkaline AA cell (typically around 3000mAh). Worse yet, its capacity drops further with each deep-discharge cycle. Based on technical data for Rayovac Renewal, the capacity of a RAM cell drops to 50% its original value after just 25 deep-discharge cycles. In comparison, a typical NiMH cell can go through about 500 deep-discharge cycles before it capacity drops to 90% of original value. (This is under controlled test conditions, so in real life your mileage may vary)

Some marketing material claims that RAM cell can be recharged 'hundreds of times'. But this is completely misleading, because it can only be achieved if you shallow-discharge (discharge no more than 25% of capacity) the cell everytime. That means you have to remove the cell and recharge it very frequently, before the low-battery indicator ever comes up.

To give an example, let's say your wireless mouse can run on a regular alkaline cell for 3 months. After switching to a rechargeable alkaline cell (which has much lower capacity), it can only run for 1.5 months. But that would count as one deep-discharge cycle. To ensure that you stay within shallow-discharge cycle (25%), you'll have to recharge the cell once every 10 days!

In my opinion, it is just not worth the trouble to 'baby-sit' those rechargeable alkaline cells, especially since you can easily buy low-self-discharge NiMH cells (such as SANYO eneloop or Rayovac Hybrid) instead.

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Customer Rating:
Summary: Chargable Alkalines are the way
Comment: I have been using my Chargeables for many years and they work great, I'm here to buy more. Rayovac also has some good ones, but these are cheaper and I have only had a few burst in the past 5 years of continuous use.

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Customer Rating:
Summary: They do not work in my wireless mouse
Comment: They do meet the specifications my wireless mouse calls for, but they just do not work!

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Customer Rating:
Summary: These are so much better than Ni cd's or Ni mh's I will never use anything else again.
Comment: These have the full 1.5 volts that other rechargables don't have. It makes all the difference in most high tech toys. I will never use a 1.2 volt rechargable again. Thank you for a awesome product.
Kevin

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