need help !

[escin]

i've found my father's power supply for his handphone.then i take the power supply and use it to charge my r/c batt.the problem is the battery get hot in a minute and the batt is not fully charge at all.the power supply rating 13.38v max7A(what it mean by max7A) and my batt is 7.2v 1200maH.

 

[Nigel Goodwin]

i've found my father's power supply for his handphone.then i take the power supply and use it to charge my r/c batt.the problem is the battery get hot in a minute and the batt is not fully charge at all.the power supply rating 13.38v max7A(what it mean by max7A) and my batt is 7.2v 1200maH.

You can't just use any supply at random for a charger, doing this is likely to damage both the supply and your battery.

 

[goodpickles]

Also put your father's power supply back...It prevents um...um arguments.

 

[escin]

my father not using it anymore.what should i do.are they posible to put some resistor to reduce the current and volt.

 

[Nigel Goodwin]

my father not using it anymore.what should i do.are they posible to put some resistor to reduce the current and volt.

Yes, that's the basic difference between a power supply and a charger. You simply calculate the resistor value using ohms law.

The current is the charging current you require, and the voltage is the difference between the supply and battery voltages. You will need a suitable large wattage (wirewound) resistor.