EV drive test prius classic 2000

Excellent test! Just a couple of suggestions:

• better traction battery instrumentation - if your OBD scanner is not able to read the 19 module-pair voltages and current, you might consider adding your own probe points and routing them out where they can be recorded automatically. In particular:
  • 50-250k ohm limiting resistors - only one side of the resistors should connect to the battery and the reverse side, go to the wire bundle that exits the battery case (if you run the test with the case on.) The resistors limit any accidental short to ~1-5 ma. This is more than enough to get a credible voltage measurement without the risk of a short leading to a battery fire.
  • Tap the current sensor "donut" - Good Prius Friend Hobbit has documented the current-to-voltage relationship so you can measure the current flow.
  • No need for temperature monitor - discharge is endothermic so the only source of heat is ohmic
  • OPTIONAL - Schottky diode protected charging wires. Separate from the sense wires, they provide a way to recharge the main pack with significant voltage. NOTE: charging is exothermic so you may want to wire the fan to run when charging.
• 12 V Bus monitor - something to track what is happening. As you've discovered, if the 12V bus drops too low, the control computers 'lose their mind'.
• Capacity test the traction battery - difficult as a pack, removing the weakest modules and bench testing them gives the minimum, remaining pack capacity. In a series battery, the weakest modules will limit the total pack capacity.

As you've discovered, the control computers work very hard to protect the traction battery from excessive discharge. In normal operation, from excessive charge. So you're typically working between 40-80% state of charge.

Was this just 'curiosity' while waiting to return the car to full service?

Do you have an interest in converting the car into a pure EV?

Bob Wilson

 

Bob, I have a prius classic with a deteriorating exhast system. What do you know about converting it to a pure EV?

 

I've heard of someone trying to convert the two-seat, Honda Insight into an EV but never of anyone trying to convert a Prius. There are some pretty daunting challenges:

• MG1/MG2 and inverter control - no one to my knowledge has reverse engineered the interface
• inadequate battery capacity - a hybrid battery is less than 10% of what a usable EV would require

It won't be cheap or fast but it could be done.

What is your background? We need to understand your technical skills to make sure we use the right terms and to discuss the technology. Also, we might want to go to an experimenter's forum like ecomodder.com.

Bob Wilson

 

Another note the current battery pack not only severely limits your range but it also doesn't provide enough power to allow mg1/2 to operate at there peak output. also adding additional packs in parallel to the current system is feasible however charging additional NiMh battery is not a task for the faint hearted...
Currently I'm building a Honda Del Sol EV and there are many hoops to jump through for an effect BMS ( Battery Management system) . Keep Playing with it ! take great caution with the Traction pack but you'd be surprised what you can do with a little hack and modding

Have fun !

Eric

 

Previous post of mine for some numbers correct me if I'm wrong:



Our Prius batteries if gen 2 upgraded are 21kw or around 28hp... Now I'm pushing nearly 31kw with additional packs so I should be around 42 hp.. Now we have the equivalent to 44Hp electrics correct? Without compromising the integrity of the system has anyone tried increasing our inverters capacity ? The electric side alone is worth 258 ftlbs of torque plus the gas side is in the 80ftlbs. If we could unlock some of this potential even with some kind of "oh shit" command. We could have some monster takeoff and early acceleration ! Just some ramblings opinions wanted.

Have fun !

Eric


Whoops old thread well maybe somebody will read it!