IMPRES vs Non-IMPRES XTS Batteries

[mhodgson]

The agency that I work with has approximately 1500 XTS3000 and 5000 portable radios. We don't typically issue a desk charger, relying on some flavor of the TPL/Motorola vehicular charger (TDN9816, TDN9176A, B or C and WPLN4208). From day one (1997) we purchased the radios with the NTN8294 (A or B) version Ni-Cd battery. Our largest single purchase of radios came in 1999 when we bought 450 at one time. Today (2009) we still have radios that come in for repair, reprogram, etc. that are equipped with 1999 code date batteries. Most of these STILL maintain 60% or greater capacity when analyzed in our Motorola BMS analyzers. In 2004, we bought a quantity of "Nused" XTS5000 radios from Motorola from a large scale event (Hurricane or some such). These radios came with IMPRES Ni-Mh batteries that were intrinsically safe and have remained servicable as they approach the five year mark. Beginning in 2006, we began to buy the HNN9031 IMPRES version of the NTN8294 Ni-Cd battery. The first 100+ were due to Motorola's inability to deliver the NTN8294 in a reasonable time frame and were offered to us as a "comparable" replacement and we paid the same price. We bit the hook....from that point on, we have bought solely HNN9031 IMPRES batteries. One might wonder why we never moved to Ni-Mh or Li-Ion, its mainly the fact that we have over 500 perfectly servicable vehicular chargers that work only with Ni-Cd batteries AND we have never had an issue with the Ni-Cd's till now.....We have begun to see a TREMENDOUS failure rate of the IMPRES batteries with 635 code dates.....primary complaint from the field is...will not hold a charge....when we place the batteries in our display equipped IMPRES rack chargers...most will not show greater than 20% capacities remaining....We even have quite a large number of 740 and 805 code date batteries that will not even achieve a 60% capacity, despite some not even being much more than a year old. When aggressively reconditioning the batteries, we dont see more than a 5-10% improvement at best in capacity. This is NOT the case with the 2004 IMPRES IS Ni-Mh batteries...when reconditioned, they typically gain 15-20% despite there age...

We do notice that the batteries that are failing the most contain Chinese cells vs older IMPRES that contained cells made in Japan....
I know that nothing lasts forever and some batteries (Li-Ion) DO have a critical shelf/operative life....however it is hard when a 1999 battery with reconditioning comes up with a better capacity than a battery seven years newer.

I am looking for feedback from users, large or small that use the same batteries and what experience you may have had with them. We have sent batteries back to Motorola and the feedback we receive is rather too wishy washy for me. Their initial comments are that "the customer doesnt want to buy IMPRES batteries"....They are scheduled to come on site in the next month to meet with us face to face and I would love to have some "war stories" from others to compare...

Thanks in advance...feel free to post here for all to read or PM me if you wish.

Mike