Dual battery charger cable?
Hi to all,
When I bought the CPX with two batteries I recived a "Y" cable for plugging both batteries to the charger at the same time.
Did other users recived the same cable? Do you know what electronics include the cable inside? How are batteries cahrged... simulteneously? swapping periodically one with the other? First charging on and then theother one? Just questions that I ask myself 🙂
I also got this cable and when I talked with a Super Soco service manager in China, he told me not to use it because it can damage the batteries.
The problem is the cable is stupid. I took it apart and there is no electronics inside. The schematics is as follows:
Positive voltage and negative voltage is splitter and connected.
Pin1 is shorted to ground (negative voltage), which makes the battery give voltage.
Pin2, 4 and 5 are splitted. Pin 2 is then grounded by the charger to switch batteries to charging mode. Pins 4 and 5 are CAN-bus interface to communicate between the charger and battery.
However, if you connect one empty and one half-empty battery to the Y cable and then connect to charger, both batteries will have their voltage leads connected which means the higher battery will charge the lower battery with UNLIMITED current (only limited by what the cable can deliver). This is very crude.
That its incredible. They supply us with a non-recommended cable!! The good thing about it is that we have several plugs for playing and making longer charging cables 😉
Thanks for your reply.
Exactly. I took it apart and used the cable to reverse-engineer the CAN communication between charger and battery. I already have lots of data about how the BMS and charger control the current to maximize battery longetivity.
It looks that there is a lot of tech in the charger! I expected a standard charger but I measured the power getting from mains and I measured non-standard or non-expected measuremtns. I posted the plots in the forum
I asked in Spain for a second charger and they ask for more than 550€!! It will be nice if you share progress 😉