This paper will trace the previous 13 year history of the varying attempts to perform field recovery on 2 volt VRLA cells that are suffering from PCL (Premature Capacity Loss). It is well understood that GNB was the first manufacturer in the USA to bring a large capacity VRLA AGM cell into the US market with their Absolyte I product, which immediately gained acceptance and substantial market share, and was obviously followed by the other US manufacturers into the market place with their own

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... products. Also as everyone here understands there have been numerous papers at this and at other conferences that at least since 1985 have documented the "early failures" with these cells from all over the world. The papers that have been presented were all from renowned authors and came from a broad range such as manufacturers, end users, and research facilities. As with any new technology there was a steep learning curve, and it was soon discovered that the VRLA battery was a different animal than the Vented Lead-Acid one that all of the authors knew so well. There were a number of initial problems associated with choice of materials, and manufacturing processes, but these were worked out just as with any new product that is developed. The old saying "time will tell" has had a lot of meaning with this product. One thing that everyone learned early on was that these cells would suffer PCL (premature capacity loss) from a multitude of reasons, with the initial understanding in the USA being that loss of water from the electrolyte or a lack of compression in the cell was the culprit. The cause or causes of PCL has been the subject of many of the papers presented through the years. This paper is going to track the development of the IOVR™ (Internal Ohmic Value Recovery) battery capacity recovery process, over the past thirteen years, and just like a child growing up, it will show the initial attempts and shortcomings, then the gaining of a better understanding of the issues, the experiments involved, and the final maturing of the process into the IOVR+™ process. It will track the lives of two fifteen year old batteries that have had various parts of the IOVR and IOVR+ process performed on them, and that have maintained their recovered capacity for up to seven years. It also will show one ten year old system (actually three strings) that we performed differing parts of the IOVR+ process on in order to determine which part of the process caused the greatest amount of recovery.