hi please can you help me i need the electronic circuit of the battery charge controller 24V/ maximum current 45A
To start, you need to know what type of battery you are using, each type has a specific characteristic.
If it is an automotive battery, look for schemes with float mode, so when reaching the maximum charge voltage you should not force the battery.
Large capacity automotive batteries can be charged by low current chargers, say 15% of battery capacity, you do not need to use a 45A charger for a 45A battery.
When using a charger with the same capacity as the battery, or something close, it is often called a quick charge, and this type of charge is generally not healthy for the battery.