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I've got a battery charger/tender that is supposed to be used to maintain the battery over extended periods when I'm not using the car - is it ok to have this connected to the battery and battery still connected to the car as I know with regular chargers, you're supposed to disconnect the battery first. The car is a 2002 Nissan March if that makes any difference.
For your little March, I would prefer to disconnect at least the negative terminal.
I do know that you can leave the terminals connected when using a trickle charger.
But I would prefer to disconnect one terminal just to be sure.