dead battery

just back from a week's vacation, despite disconnecting the 12v battery, and despite charging it up a few hours right before leaving, it was down to 5v when I returned...  Not a problem with the car, just a weak battery.  It should be able to sit disconnected for a week without going dead.  Anyway, I've found I can easily jump-start it by touching a quarter across the DC/DC contactor, which sends 13v from the 160v main pack to the aux battery and gets everything up and running.

In other news, I've begun tearing the upper motor mounts a little bit.  A redesign has already happened in my head, just need to make it happen in the car now...  Basically I want to replace the upper mounts which are simple cylindrical rubber vibration isolation mounts with the original beefy rubber engine mount that was in the car.  I've ordered the parts I need, but it will require fabricating a new end plate to connect the motor to the new mount.  And will require pulling the motor/trans out again.  That's ok, there's a few other things I want to do in there too that will be a lot easier with it all out.

Next update will probably be in a few weeks, I'm not going to tear it apart until after the new year, and after I have a chance to get the Big Red Van's transmission looked at (it's slipping a bit).  In the meantime, I've lowered the motor amps to 350a to save from doing more damage to the upper mount.

a few little updates...  It's been running well, the heater has been fine even in the cold 30 degree mornings lately.  And that's just with one element switched on.  I can't imagine needing the second one!  Though it is garage kept right now, which helps keep it not as cooold overnight.  Less to have to warm up.

Anyway, I've been tracking my ah/mile (amp hours per mile) through the controller lately, and I've noticed about a 10% difference between the 30 degree morning run to school, and the 55 degree afternoon pickup.  All else is pretty equal but the temp.  Not too surprising, batteries don't really like cold weather.  Even worse case usage, I've still got an easy 45 mile range without flattening the batteries (you really aren't supposed to take them further than 80% discharged) which is plenty for my daily routine.  Best case in the summer should be closer to 60 or so miles.

yesterday I wired the brake vacuum pump through a toggle switch so I can shut it off in parking lots for that cool 'silent EV effect' and for those times when the pump sticks on...  I plan to do the same to the motor blower, but it's not nearly as noisy so I'm not feeling quite as urgent about it.

it's getting driven between 20-40 miles every day right now, charging up for what I calculate to be the equivalent of ~$1.30/gallon when normalized against the Honda Odyssey it replaced.  And working just fine as my main kid transporter!  And this is paying a pretty high $.24/kWh with PG&E, should be able to pretty easily cut this in at least half with either solar, or a dedicated E9 rate meter, or both.  Down the road a bit for those...