Greetings all,

This is my first post, so please forgive me if this isn't posted in the right location or additional information is necessary.

I am trying to modify a Ryobi P119 charger, as it is worthless in its factory form. I would like to increase it's charging power from the stock 6.5w to 20+ watts. The PCB and traces appear sufficient, but I am not sure which resistor sets the amperage. Connecting a 30w 20v DC power supply results in approximately 12w output.

Attached are photos of the PCB in question. Thank you in advance for any assistance.

 

If the goal is to charge lithium batteries much faster, I suggest understanding that faster charging often leads to overheating, and either fires or explosions followed by fire. The charge rate for power tool batteries is already a compromise between battery life and operator impatience. And without the actual circuit, considering the complexity and that there are two ICs on that board, there is no way to know which resistor might affect the charging rate.

 

Thank you for the response. The power tool cells and batteries in question routinely charge at a 4amp rate and and rated for such.

 

Thank you for the response. The power tool cells and batteries in question routinely charge at a 4amp rate and and rated for such.

OK, so then you need the correct charger. modifying that tiny charger PCB would be a serious challenge