How do I use a car battery charger?

WellKnownSid

m0bov said:

Always best to disconnect battery from car to avoid damaging the alternator or ECU.

Up and down the country, every single day, thousands of batteries are charged, boosted, or load tested whilst still connected and no-one damages their alternator or ECU.  And why the ECU specifically and not one of the 25 other modules permanently connected to 12V?

BlueonBlue

If the weathers bad or its late  at night etc start the car with a jump starter/booster to get going ie. so you can start and drive go complete whatever you must do.

Ideally drive it for a period of time to charge the battery but if you cant run the engine long enough then just jump it again when required and then give the engine a good run so the alternator has time to charge the battery or use your smart charger  at home via the extension lead when it suits.

The links to a Gooloo/Grepro jump starter are above in this thread they are your get out of jail tool .
The smart charger you bought will stop you going back into jail but the jump starter gets you out of jail.... anytime  anywhere .

nologo

connect your charger to the battery, leave the charger under the bonnet, run the 3 pin plug to the underside of the car, put the extension lead socket on a  plastic sweet box(ie quality street) to keep it off the ground on case it rains,  write a big note (A4) note & tape to steering wheel to remind to disconnect before driving off, regards

nologo