I have an idea about making my own PHEV system. I was thinking about using ebike aluminium case battery. Something like 5 48v (Product) in serie which would give arond 250v. Instead of using a enginer converter, I could use a solid state relay to give small burst of current. With an arduino board and an obd reader, I could control when to slow the charge or stop it. Anyone has gone in this way? Sylvain
Hi Sylvain, Basically this is the PIS system. But of course they have done a lot of programing to optimize it. Thanks, Dan Lander
How many A/hr in those 48 volt packs ? will you charge each pack individually or what your thoughts on that ??
The bike packs are usually about 10 amp hours. the state of charge drift systems that just use a big contractor to connect the second pack never seemed to work very well on gen 2. If he is trying on gen 3 it could be even worse.
The pack are 10ah. The charging would be with the 5 charger coming with each battery. The battery would be disconnected from each others by relays when charging. From the answers I got, the contactor base method does not seem very promising. Perhaps it is simpler to got the engineer / md tech way...
Ok, I had another idea. Using 4 48v in series lifepo4 battery pack. Use a 5th one. But instead of putting the pack in serie, it would power an ebike brushed controller that can output variable voltage. This controller output would be in serie with the other 48v battery pack, that could allow to control the charging power applied to the HV battery...
Not sure if the controller idea will work or not but I can tell you this. You could charge all the bike packs simultaneously without removing the series connections. If the 5 chargers have 3 prongs on the ac cords , break off the third prong. Now you can connect the chargers without removing the series jumpers. I have done this a few times and it has worked fine.
I like your novel idea, but wouldn't another problem be the short travel distance this high voltage, 10AH pack would give you before you need to plug the 5 chargers in again?
Indeed, but I would use a combination of relay to start the parallel charging. The chargers would stay permanently in the car.
240V, 10AH, that gives you about 2kWH power. but would it be the case that when the voltage of hybrid battery get close to your add on battery, the charging current will get very small or even stopped. For example, if the hybrid battery charged to 230V and your add on battery drained to 235V, there should be almost no net flow of current. In this case you are leaving maybe 1kWH or more cannot use until your hybrid battery (or the whole system including your add on) getting lower voltage.
