Bob,
Sulfation, I'd say. Try EDTA. Trailhead Supply. See Home Power marketplace ad for contact info. If it's not sulfation then maybe it's simply diluted electrolyte(accidental, or intentional) which would make the batteries have lower performance AH wise but should last a long time (plates hold up better in a less acidic solution). Years ago I received some Hoppecke lead acid batteries direct from Germany to make good on a bad batch of NiCADS. The Hoppecke LA's intentionally have a max SG of 1.240. Very big cells (330lbs for a 2v cell) and evidently have a very long life, as I am using them still in my barn/shop 16 years later and they act like new despite a pathetically low charge rate. These cells are rated at 2,000 AH @ 100h rate. I am charging them with 35 amps of PV with the occasional 75 amp charge when the gen is on. I have never heard much good said concerning Interstate deep cycle batteries. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of bob Sent: Tuesday, June 29, 2010 6:53 AM To: 'RE-wrenches' Subject: [RE-wrenches] Interstate UL-16 HC problem I have 2 systems that I am trying to correct that another local dealer has installed. This one is 2 strings of (8) UL-16 HC Interstate Batteries, 16 batteries total. We cannot get the batteries to charge over 1.225 despite discharging them and generator charging them till everything shut down. This is a 48 volt system with a Magnum 4448 inverter. He also has (6) 175 watt Solar World panels on a manual tracker. (spends all day tracking the sun) He is adding 2 more this summer. The controller is an MX-60. I have moved the Magnums settings to 1600 AH battery bank size to allow for the inverter to have a longer absorb time to help it finish charging and get to a full battery. It's not working; we have 1 cell at 1.240 and the rest at 1.225. These have not been cycled hard if at all, I am going to suggest that he cycle them several more times to see if anything improves after that The other system has the same problem with a different inverter! So it's not inverter related, but I am at a loss. I have not used Interstates before and want to stay away from them in the future. Any other suggestions? Thanks, Bob Ellison
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