Ok, tot it'll be gd to share wad i experienced.

Recently replaced current one with Delphi Lockheed (freaking most expensive cherry i haf bought 190$! for a car batt). I know there r more expensive ones out there which are completely dry cell (racing use)and cost much more....

Anyways, u should keep the engine running while doing dat cuz anything more than approx 10 mins of total disconnection will 'reset' the ECU. Dun ask me if its a total reset but i believe the chip needs fresh inputs for benchmarking of peak n min fuel mappings etc etc again to run normal.

Wad happened to me was the first few cranks saw the engine dying off almost immediately apart from the normal DSC and anti-skid lights coming on. The later 2 can easily be solved by turning the steering wheel full left n right a couple of times plus a bit of driving. Know that the auto window function on the driver's side will not work initially too until abt half an hour later. Ok, back to the engine dying problem, all u need to do is drive the car ard for about 10-15 mins making sure u rev the engine up to red zone for the ECU's benefit or so to speak for at least up to third gear. Even after doing all that, my baby still ran weird at idle and it was only after a little more driving did the rough idle problem went away.

This is a common thing with many cars and just tot of sharing them for those who dont already know. Dont be alarmed and immedaitely call for a Tow Truck ye...

Cheers
NEON