Hi John,

Thanks very much for your email and the opportunity to keep you supplied with rechargeable batteries. I can certainly help you to be "the best provider for properly operating batteries" to keep your wife's camera working at peak performance.

There are several challenges that you are probably experiencing:

1. Four batteries in a set - any device that uses four batteries is a particular challenge because the batteries must all be performing equally to optimize their performance as a four cell unit (same thing with a battery pack). The issue here is that one of your batteries in each set is likely exhibiting more self discharge than the other ones in the set, or is a weaker battery. Most battery manufacturers QC process accepts batteries as having passed their internal tests if they are in a certain range of performance. On the other hand, one battery in a set might just be "bad" and need to be recycled. Basically the rechargeable battery version of the weakest link in the chain.

2. Batteries must be charged fully - all batteries need to be charged fully and individually to get the best performance over time. You have already described this with your comment on your newer charger performing better than the ones that you have had in the past - the new one has four charge channels, and charges each battery separately as opposed to in a pair. If you put a pair of batteries in a charger that charges them in pairs, and one is less charged than the other, they will both only be charged as much as the one that has the greatest charge remaining - this means that one battery will not get charged fully.

3. Higher capacity can mean higher self discharge - generally the higher the capacity in a battery, if all else is equal (same manufacturer, same chemistry) then the higher capacity battery will also tend to exhibit higher self discharge i.e.- 2100 GP NiMH batteries will generally maintain their charge longer than 2700 GP NiMH batteries. Battery manufacturers have not made that much real progress in this give and take performance issue for many years.

4. To get the most of your current battery and charger investment I recommend that you get a good quality but inexpensive rechargeable battery tester like the one here http://www.greenbatteries.com/ecunbate.html then fully charge your batteries and test them in this battery tester. You will be able to tell which of your batteries are misbehaving, right away or in a few days, and then set the weak batteries aside in groups (if you have more than one) and keep the best performing batteries in groups of four for your wife's camera.
Another solution is to get a charger with battery analysis features like the LaCrosse Technology BC-900 Alpha Battery Charger and Recovery System http://www.greenbatteries.com/bcalbachandr.htm but that is much more involved and just an option for those that really like to get detailed testing results for their batteries. For example, this charger an analyzer gives the battery test results numerically in specific mAh ratings.

5. Charge your NiMH batteries closer to the time they are to be used - this will reduce the self discharge issue for the current batteries that you already have available.

6. Use Ultra Low Self Discharge (ULSD) NiMH batteries - there are newer NiMH batteries available, just in the past year or so internationally, and they are becoming available in North America more and more. ULSD batteries are generally about 2000 to 2100 mAh in capacity but the manufacturers assert that they will retain their charge up to 95% for a year. My experience with testing several brands so far is that this is a bit of a marketing statement but they are certainly better than the older NiMH battery chemistries. You will also notice that they are not the highest capacity available! We carry the Hybrio brand in AA and AAA and will soon get our own greenbatteries.com brand of ULSD NiMH batteries that have a more conservative performance claim. I prefer to under promise and over deliver. Time will tell if these batteries are all they are advertised to be but a battery guy like me gets pretty amped up with new battery technology coming into the market. (pun intended)

7. Use CRV3 li-ion batteries - wanted to mention them but the potential downside is that I am not sure if your wife's camera can even use them and these batteries require a specific dedicated charger. The potential upside is the self discharge is very low indeed.

Hope that helps.

Sincerely,

Curtis

Responsible Energy Corporation
Curtis Randolph - CEO
16157 Galena Meadows Drive
Reno, NV 89511
phone 800-790-7866
fax 815-301-3958
cell 775-722-9901
www.greenbatteries.com

-----Original Message-----
From: John
Sent: Thursday, January 11, 2007 3:57 PM
To: curtis@greenbatteries.com
Subject: A Concern

Dear Green Batteries People,

for the last several years you have provided us with our batteries and battery chargers. We are now on our second charger which is a much improved instrument relative to our first NiMH charger. I am writing however to comment on the batteries received as part of our most recent order.
In October--billing date was October 9th--we ordered 12 GP batteries, 4 of the 2700 series and 8 of the 2500 series. During October and November we went through the conditioning period; during the latter month we used them regularly in a digital camera, finding that each set of four would last for one day of use. (We were traveling, and the camera was used daily.)

Now we are home, and the batteries may sit for up to two weeks in their plastic cases before they are put into use. (They are recharged before storing, so they will be ready for their next use.) When accessed, we find they have discharged in the interim. This has now happened regularly over the past month. In the past we were satisfied by the performance of the GP batteries and got long life performance out of the 2200 and 2300 series. So what is the problem?

My wife is the picture taker, and I am responsible for providing her with properly operating batteries. You cannot believe how frustrated I am. Is there a different provider for the GP batteries? Or has the quality management system of the provider gone to pot? I have a problem, and I need a solution.

Thank you,

John