D4 battery charging query

HI,
Have just purchased my first discovery 4, 2014 model, message appears warning ''low battery start engine", (car had a new secondary battery fitted last year), question being can i use the older style battery charger or does it have to be a smart charger?

Many thanks in advance for any help

Is the message referring to the main starting battery? If original it may have failed. Can you measure the voltage at the starting battery? Should be at least 12.4 volts. Battery voltage should not be low so something is not right. Maybe alternator is not charging.
I think you can use an ordinary charger to bring the battery up to where you can start the car. Just dont leave it connected for too long. Then with the engine running check voltage at main battery. Should be over 13 volts, maybe up to 14.

Some d4 had an agm battery as their main starter battery.
You almost need to treat batteries as a consumable.

Many thanks for your advice

If the battery is AGM a classic charger is not good

I put an optimate charger on mine if it’s not been used a lot or short runs , the battery can have more taken out than goes back in, obviously if the battery is old it may be time for a new one.