it has been suggested that perhaps another thread should be started
on the topic of how high temperatures effect battery life.
because of the unusually high summer temperatures witnessed by many folks across the globe this year, some of which depend on batteries for their energy storage needs, and based on everyones desire to get maximum lifespan out of those batteries i thought maybe a discussion was in order.
so here is a few links
http://www.apcmedia.com/salestools/SADE-5TNQZQ_R3_EN.pdfwhile this link relates to ups systems which usually use vrla/gell/agm or some sort of sealed battery, the link also shows some data for flooded cells... apparently operating in ambient temperatures over 91 degree's F starts to have a toll on battery lifespans. as temps go up 1 degree C (1.8F) the lifespan decreases by 2.5% per degree C. it also relates to the increased need for watering under those conditions which ought to be seen as an indicator that maybe the bank is being operated at in elevated and deleterious manner, giving rise to the one maintaining the battery reason to investigate and take measures to alter the temperatures by whatever means are necessary even if it might mean discontinued use of the battery until temperatures can be lowered. (this if optimizing lifespan is of primary importance, and realizing of course this might not always be practical)
http://www.gillbatteries.com/pdfs/Flooded_Service_Manual.pdfa bit more info in support of not operating at temperatures over 120F
and some info on increasing battery capacity at higher temperatures, higher levels of plate corrosion etc.
http://www.artec-ingenieria.com/pdf/guias_megger/New_BatteryTestingGuide_en_LR.pdfpage 16 Temperature, has the relevant info, operation of a battery bank in temperatures over 95 degree's F will cut the lifespan by half, 20 year batteries will become 10, 10 year batteries will become 5 year batteries.. this paper is actually excellent in my opinion on other facets of battery maintenance, charging, testing etc.
btw, at temperatures of 113 and above the 20 year battery can effectively become a 5 year battery... something to consider? i think so.
we can go on with research, however it would seem there is nothing to be said in favor of higher temperature operation of a battery, and much to dissuade one from doing so.
while the batteries are not operated continuously at elevated temperatures typically, it is not likely that the lifespans will be cut as dramatically as reported (provided everything else is in order) however the plate corrosion will be accelerated and this is not reversible
bottom line, if one has a significant investment in a battery bank or is anticipating such, he ought to seriously consider some means of temperature control for his battery room so as to not allow operation at elevated temperatures. maintaining room temperatures below 90 degree's F probably being a reasonable upper limit.
thoughts?
bob g