[MSCW list] Battery dead after leaving headlights on for 20-30 minutes on

[Kent Shaw]

Batteries for my 1999 Miata were lasting about two years but I just don't
drive it enough to keep the battery fully charged (just 25K miles on the
odometer) so I may be a special exception.  One thing that I did to extend
life was to buy a  Battery Minder (not Battery Tender) and recharge the
battery every couple of months.  The Battery Minder has a unique
de-sulphation cycle that tends to extend the battery life quite a bit and
has a reputation for being able to bring dead batteries back to life.  It
also has a temperature sensor for the battery to keep from overheating the
battery during the recharging cycle.  You have to specify whether the
battery is flooded, AGM, or maintenance free when you connect the battery
because it has a different recharging procedure for each type.  These are
pricier than other battery chargers but have endorsements from several of
the battery manufacturers.  I am over the two-year mark on my last battery
so pleased so far.

Kent
=========================
The car was bought in September 2009, so it is 4 years old. ?After a jump
start and driving it around, the battery charged up and the car starts.
?I've been doing a little bit of internet research on battery drain problems
in 2010 Mazdas and am of the opinion that the stock, non-maintenance-free
battery in this car leaves something to be desired. ?Some people have left
an interior light on somewhere for a couple of days, and that also kills the
battery.

Here it's recommended to replace the battery every 4 years, which I'm going
to do:
?http://www.carcarekiosk.com/video/2010_Mazda_3_i_2.0L_4_Cyl./battery/replac
e_battery