When needing to know the amount of charge time that your mobility scooter battery needs you should always check the documentation that you received with the particular make and model of mobility scooter that you own.
You also need to take into account whether this will be the very first charge of your mobility scooter battery or whether it will be a charge after having already used your mobility scooter.
Even if you have a friend that uses mobility scooters, don’t go by what they might recommend you should do because there’s a great chance that they own a completely different model to the one that you do.
You want to get the most life from your mobility scooter batteries that you can, both in terms of the distance that you can travel and the overall lifetime of the batteries before needing to replace them.
You can find information on how to charge a mobility scooter battery by following the link, and combining this with the instructions and recommendation in your documentation will help you to understand how long the batteries need to be charged for.