You might want to consider adjusting a new battery's electrolyte to "tropic blend" specification. This works well in places like Florida and the southwest (and here). Warm electrolyte is angrier than cool electrolyte and continues to take it out on plates and paste even when it is supposed to be kicking back when the battery is resting. This adjustment is best done when a battery is brand new and performed by a battery manufacturer or distributor. They can also amplify the benefit (and slight loss of performance) inherent with changing to a tropic blend.
