On 2 Jan 2014 at 6:53, Bruce EVangel Parmenter wrote: > The 'starting' marine has a higher CCA (cranking amps) which means the > plates are thinner and shorter life).
One way to improve your chances of getting usable marine batteries is to look for batteries rated for minutes of reserve capacity. A battery rated for [cold] cranking amperes is almost certainly an SLI battery and NOT a deep cycle battery (or even an imitation of one). > The group 24 size batteries are what the golf courses buy for their > golf carts. Perhaps in CA, but not around here, unless things have changed radically in the last few years. > These are usually the 6V golf cart batteries (similar to a Trojan T- > 105 in size and performance). This isn't the case for G24s. You may be thinking of group 31 batteries. It's true that G24s have nearly the same >footprint< as a golf car battery. A BCI-standard GC2 is 10 3/8" x 7 3/16" and a BCI-standard G24 is 10 1/4 x 6 13/16. So a G24 will fit where a golf car battery fits. However, G24s are shorter (as in height) - 8 7/8" vs 10 5/8". They are also quite a bit lighter. A typical 105-minute golf car battery weighs about 65lb, but a G24 is around 45lb. Weight is roughly proportional to capacity, so a G24 has just over 2/3 the watt-hour capacity of a golf car battery. The marine battery closest to a golf car battery in performance and capacity (though not in shape) is a group 31. It weighs about the same, has about the same amount of lead, and has about the same (usually slightly less) capacity measured in watt-hours. However, note that if you use an >equivalent voltage single string< of G31s, it will weigh half as much as the same voltage of golf car batteries, and have (less than) half the capacity. If called on to produce the same current for driving, the G31s will have a much shorter life. (You can usually measure their life conveniently in months.) You can get close to golf car battery performance by using two same-voltage G31 strings in parallel. However, there is no advantage to this unless you have an unusually cheap source of G31 batteries. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
