Do I really need to disconnect my battery before charging it?

The instructions that came with the battery charger I bought from Argos yesterday say 'disconnect the battery from the vehicle before charging, to avoid possible damage to the alternator'. That could have quite interesting results without a slave battery. Is this normal?

Asked on 28 September 2013 by MD, Ringwood, Hants

Answered by Honest John
Yes. You bought the wrong type of charger. You should have bought a 'Battery Conditioning Trickle Charger'. Nothing needs to be disconnected when using one of them.
Similar questions
As I will only be doing short infrequent journeys should I buy a solar battery trickle charger. If so which is best and easiest to connect please. Possibly not connecting to the battery terminals. Will...
I have recently bought a 2014 Ford Fiesta 1.0 Ecoboost - my first car with a stop/start engine and battery system. In the winter, I use the car very little and would like to top up the battery using my...
I have a Nissan Qashqai e-Power. Can I leave my car at the airport for 2 weeks without the the battery been drained?