My wife bought a new Kirkland battery from Costco in December of 2005. 1000 cranking amps/900 cold cranking amps. The purple sticker in the corner on top of the battery says 10/05 ... so I assume it was shipped from the factory in October of 2005.
The battery operated fine until December of 2010, when she started having problems starting her car. We would use a portable charger to boost the car and she could always return from her short shopping trips but I figured the battery must be closing in to the end of its life.
Then, the day after New Year in 2011, on a bitterly cold day, she left home and drove 2 miles to the grocery center. The engine died twice, being restarted by passing motorists who gave her boosts and/but when she got there, the engine died for the last time and she phoned me at home to get help.
When I got there, I was shocked to find the battery absolutely stone-cold dead. Not even a slight glow from the dome light.
I boosted her battery with my own vehicle for a full half hour before even attempting to start it.
Her car started up fine and she drove it home and then I did some closer checking on the charging system. Even though the charging dash light didn’t come on, the alternator was definitely putting out almost nothing. After taking the alternator apart I found all the solder connections to the bridge rectifier contacts were badly deteriorated and “rotten”. One of the “diodes” was actually shorted from overloading on single phase output.
I replaced the alternator and switched batteries with a spare and then slow charged the Kirkland in my basement for a full two weeks with a voltage cap of 15 volts. I checked the specific gravity on the cells every day ... until they all showed a top reading. I don’t remember if I added any distilled water to any of the cells at that time.
I put the Kirkland back into operation after this treatment and expected maybe another year of service, tops.
Yesterday, my wife said she’d left the dome light on for a full 24 hours and now the car wouldn’t start. The dome light was still glowing normally but the starter merely chattered.
I thought this was pretty remarkable. A battery of this advanced age ... still able to light a bulb for 24 hours and have enough to make a starter solenoid chatter?
I put a charger on the battery, set current limit to 7 amps with voltage capped at 15 volts.
After one hour, the charge was still going at a full 7 amps.
After 2 hours, the charge rate was still 7 amps. Good grief! It was showing NO SIGNS of being an old battery; still taking charge like a new one.
If this battery lasts until December 2016, it will have produced for 11 full years.
I have never seen any battery compare to this!