Ryobi40V

This is a basic analysis of how a Ryobi 40V smart charger (model number OP403) communicates with the battery's BMS to enable the charging FET.

Electronics

Pictures of the charger PCB are below:

PCB top side.

PCB bottom side.

The wall wart adapter is a 42V 1.5A rated switching converter, listed at 84W max from AC (though output is max 63W). The wall wart does the necessary CC/CV current limiting, with a ~44.2V open circuit voltage output when no battery is connected. Output is switched to the battery though a MOSFET.

Charging Sequence:

File:Ryobi 40VChg Sequence Main.jpg

Battery insertion to charging start sequence.

Data detail:

File:Ryobi 40VChg Packet.jpg

Data packet detail.

Photos

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  CCR v1 prototype in regenerative configuration

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