Peter, To your first question: fully recharging any lead acid battery as soon as possible will give you longer cycle life. Waiting to charge and/or deep discharges lead to shorter life. If you have the proper 3-stage charger, leave it on the battery until you needed to use the forklift.
100% SoC voltage after appropriate rest varies among batteries. I have worked with a few forklift batteries in off grid homes. Flooded rest at 2.117 VPC. For AGM about 2.183 VPC. (77°F) As I have posted in the past, most AGM battery can easily withstand up to 5C initial charge rate. Proper voltage and time is the more important factor when charging AGM's. Larry Crutcher Starlight Solar Power Systems On Nov 27, 2012, at 2:31 PM, Parrish, Peter wrote: We recently purchased a battery powered forklift, with 24 ea. 2V batteries. Approximate dimensions: W=5", L=6-3/16", H=~21" (hard to tell). Enersys is stamped on the top. The battery supplier claims the batteries are "24-85-13" but this refers to a 24V battery as far as I can tell. He also claims that the batteries are rated at 510-550 A-hr. I am assuming that the lower number is for 6 hours discharge. I would like to know more about the batteries. Also, how to discharge / charge them. Should they be run down to 20% SOC and then fully charged? What if we don't use the forklift for a week at a time? Based on my experience of using AGM batteries, it would seem that the Bulk charging rate should be some percentage (e.g. 20%) of the 6-hour ampacity, then there is a constant voltage absorption charge (e.g. Vabs=2.385 V), and a switch to Float when the charging current drops to some low percentage (e.g. 0.5% of capacity), and the Float voltage being 2.125 V. Again everything at 25 deg C. It seems like the forklift guys like to refer everything to a 6 hour capacity, which may be related to the maximum typical daily usage. What is the relationship between Voc and SOC after resting the battery for 6 hours at 25 deg C? Thanks in advance for your help, guys. - Peter Parrish Alternative Energy Department College of the Canyons [email protected] O: (661) 362-3888 C: (323) 839-6108 _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
