Valve-regulated lead-acid batteries of AGM design are widely used for back-up power in stationary applications like telecoms, data centres, UPS, etc. The discharge of AGM batteries is usually at constant power mode, requiring highly porous and sustainable microstructures of the active materials and sufficient amounts of sulfuric acid. Recharge profiles typically comprise constant current, floating, pulsed or boost charges. This charge regime is supposed to ensure long battery performance even at frequent power interruptions. Unfortunately, AGM batteries under these conditions demonstrate shorter service time (or cycle life) than claimed by the manufacturer (design life).
They often can’t be sufficiently charged before the next discharge step, or spend a relatively long time at open circuit. Undesired battery degradation processes occur, resulting in reduced capacity and shortened service life. Some processes are reversible (sulfation, electrolyte stratification, passivation) while others are not (water loss, heat evolution, corrosion, PAM shedding). Affected batteries must be maintained more often than expected, leading to increased operational costs, with some having to be scrapped and replaced. Recently, WaveTech developed innovative technologies, and automated equipment for rejuvenating batteries has been realised to recover battery capacity and functionality. As a result, AGM batteries can live much longer than usually observed in real-life conditions. Rejuvenated batteries can get a service life even close to LFP batteries without the risk of fires and have a long service life at lower costs. Charging can be fine-tuned based on battery condition. Wavetech can evaluate battery condition fast and precisely. The new equipment developed by WaveTech was successfully field tested by large UPS companies in various countries. On teardown analyses and material science studies performed at the Battery Science and Technology Centre of WaveTech in Sofia, Bulgaria, we estimated that the rate of recovery was over 85% for two to four year old 12V batteries.
Additionally, the technologies developed by WaveTech reduce the rate of water loss, corrosion, and heat evolution. No changes in phase composition were observed. The results from the special CCT charge pulse profile used and the unique BARS recovery procedures we apply will be discussed during this presentation. The new technology of WaveTech allows battery users and owners to extend the service life of their batteries by two to three years.