Double Battery with Selector Switch?

[tpripps]

Has anybody ever explored the possibility of having two stock battery packs that can be toggled between with a selector switch, reminiscent of the old Chevy pickups with dual tanks. The switch would control a contactor junction. This way you wouldn't have to be clever with programming (I'm not) and you would effectively double your mileage. Obviously you'd have to toggle for charging too. What do you think?

 

[MickeyS70]

Has anybody ever explored the possibility of having two stock battery packs that can be toggled between with a selector switch, reminiscent of the old Chevy pickups with dual tanks. The switch would control a contactor junction. This way you wouldn't have to be clever with programming (I'm not) and you would effectively double your mileage. Obviously you'd have to toggle for charging too. What do you think?

Interesting idea, but the added weight means you certainly won’t double the range and the actual gain may be underwhelming in the end. Finding one decent stock pack is challenging but two will be a real struggle, especially as they have to be matching capacity.

Assuming you manage to get two identical batteries fitted and connected it could actually work:

Charging:
Pack A will charge until the 4.1V and SOC will be set to 100%.
Turn off the car
Switch to pack B, do a BMU reset (disconnect 12V supply)
BMU will set capacity according pack B voltage
Charge pack B to 100%

Driving:
Drive on pack B until tortoise lights up (around 10% SOC)
Stop and turn off car
Switch to pack A and do a BMU reset.
BMU will set capacity according to pack A voltage
Drive on pack A.

Mickey

 

[tpripps]

Yeah, I hadn't considered the added mass of the battery. They're relatively small and light on my Prius but that's obviously a different animal. I just really like the look and bare bones feel of the i-miev that I was hopeful that there was a solution there. I have a ~55mile (round trip) commute everyday so I was hopeful there'd be a way to get this car to that range but I may have to consider other options. I even talked to my boss about getting a charger installed at the office. He wasn't on board.

 

[MickeyS70]

Yeah, I hadn't considered the added mass of the battery. They're relatively small and light on my Prius but that's obviously a different animal. I just really like the look and bare bones feel of the i-miev that I was hopeful that there was a solution there. I have a ~55mile (round trip) commute everyday so I was hopeful there'd be a way to get this car to that range but I may have to consider other options. I even talked to my boss about getting a charger installed at the office. He wasn't on board.

All you need is an outdoor socket near your car to plug in your ‘granny charger’…

 

[Gary12345]

You also need to change the comms plugs that control and communicate with the battery - its not exactly just a + and - wire.

 

[tpripps]

Eh, all this is probably beyond my EE ability. Guess I'll just buy a Geo Metro and slap a boat tail on it ;-). Thanks for the feedback, everyone.

 

[pbui19]

what about pulling the old Enginer Prius extender concept ? back in the early days, Enginer added a 4kwh 48v pack and a DC-DC boost to ~265vdc or so, and fed the stock Prius' pack directly to extend the effective electric miles...

https://www.enginer.us/

 

[suziauto]

yeah , I bought a burnt out wreck with that concept done to it , the funny thing was, the pack in it was a very good pack to start with! I have been reading these posts and to be honest , if you want the 30Kw pack just send your cars to one of the OZ Electric Vehicles authorized installers of if theres none near you suggest it to a local EV workshp and get them to sign up. WE do not send these to owners as a DIY " KIT " as its not for amatuers

 

[jray3]

hey @tprips, there was a hacker in Europe (Croatia, IIRC) who did this double-pack thing about 8 years ago, but concluded that the car was overloaded and impractical, given the lost rear seating and cargo capacity. Until I get my 30 kWH upgrade done, I'm loving life with the Pusher Trailer. Check out it's debut video. More to come this summer.

 

[MickeyS70]

I have been reading these posts and to be honest , if you want the 30Kw pack just send your cars to one of the OZ Electric Vehicles authorized installers of if theres none near you suggest it to a local EV workshp and get them to sign up. WE do not send these to owners as a DIY " KIT " as its not for amatuers

In all fairness, your upgrade package is superior to anything else available presently, however few triplet owners want or need a 200+ km range and even fewer think it’s worth investing that amount considering the age of their cars and more importantly what else that sum can buy you these days.