Achieving ready light without BMS connected, a REX and some flood

[drcat]

I finally bought a new toy for myself as a Christmas present
Meet the new me with a 2012 c-zero / 32Ah health, 133kkm.

So far I've figured out that:
-hobdrive is not working for me: connects but unable to read cells
-OBDZero works just fine (you can find that on playmarket) with ELM 1.5 from a well-known Chinese site
-Delphi 150 works fine with Autocom (< $50 for the bluetooth one cheap clone from the same site): reads errors, data streams, erase errors from all the blocks with no issues. Oh and it also can do battery balancing (says takes over 8h).

So the only thing I'm unhappy with is the mileage so I'm thinking of two things to make myself less sticking to chargers:

- a REX. 1-cylinder diesel engine - may be even air-cooled under the front hood paired with a powerful automotive alternator ~230A @ 14V are pretty affordable - will give me (assuming loosing some power on a dc/dc converter) over 3kW at 360 volts for direct charging. Or by removing the diode bridge and voltage stabilizer, a transformer could be used then need to add a diode bridge and stabilize the output to 360V (with pwm probably), link that to chademo contacts directly by overriding its contactors and here we are - I think that's a bit better solution. The guide on how to enable chademo power pins is available at this forum. Need to involve some very simple micro-controller to add some security... arduino probably (don't hate me yet I've made tons of stuff with those - from LPG controllers to cruise control devices, all of them still doing their job ). This should extend the range a bit or allow to slowly crawl to the nearest chademo charger when needed.
The reported power consumption at 50mph / 80 kmh is 25A. 25A @ 360V is 9kW. we'll add extra 25km during every hour of driving. Thus makes possible to drive @25 km/h while the diesel is in the tank. To get a full-blown hybrid, it needs a much more powerful engine and alternator. That would be costy. An intermediate solution could be using like 15hp engine plus 2x250A generic automotive alternators - I don't think its possible to painlessly put more under that hood. If you guys know any specific vendor / model of a widely spread automotive alternators (24 or 27 or 42 volts or even higher works even better for sure, may be from a junk yard - let me know please).

-a fully custom battery - I wonder if anyone tried to or even succeeded achieving "ready" state with only power cables connected and CAN output spoofed from BMS to get it to the ready mode. From what I read at different places, its a tricky thing to make it understanding over 50Ah capacity so it could be easier to use a 3rd party BMS for balancing / charging. Ideally, I wish to kick out all the proprietary modules from the vehicle one by one - starting from battery. Would like to only keep ABS and airbags. Screw all the rest
Its not looking very tricky if it is not very picky, i.e.
-enable a pre-charge contactor
-wait a second and measure the voltage at the output
-if voltage is over 300, enable the main contactor
-if not, wait for another second
-if still not, burn it down (or give up) - this should be configureable with a jumper
But I think it needs CAN spoofing

It's a hobby thing for me so I don't care much of keeping it up and running the whole time for now.

 

[JoeS]

drcat, congratulations on your purchase!

Before you do anything to/with the car, DRIVE IT! Get a feel for what works and what doesn't, and especially note how simply driving gently and slowing down has a dramatic effect on how far you can go. We have a saying around here: "Range is whatever you need it to be". Don't be put off by the the car's apparent range, especially now, as it drops significantly in winter. For example note, that when you turn ON the car's heater, your RR indicator will drop by 20%! Solution is to wear warm clothes and use the seat heater, as its consumption is negligible - the biggest issue you'll find is condensation on the windshield and if you read some of the posts about winter driving there are schemes to mitigate that.

Don't even think of a diesel REX - you own an electric car, not a hybrid! That said, on this forum you'll find a successful ICE 'pusher' solution by jray3 that worked, the only mod to the car being the addition of a trailer hitch.

There are many discussions on this forum regarding possibly upgrading or supplementing the battery pack. All were quite a few years ago when there wasn't anything else available and any mods required a LOT of time and energy and cost. Biggest stumbling block is what you pointed out: spoofing or circumventing the car's present communications.

I think that you might find that the i-MiEV's range, even with your 32Ah battery, is sufficient for most of your local driving needs. Again, become comfortable with the car the way it is presently configured before undertaking any mods - which is not to say that contemplating and researching is not to be discounted. Have fun!

 

[Tiborx8]

Hi,

if you are in search for a tiny but powerful generator, take a look at the 2nd gen GM eassist starter-generator, used in several cars like the Buick lacrosse hybrid (parts nr. 24261691 AA), mind you it has a rather tricky resolver.

As for the battery saga: the i-miev and the 2014 leaf works according to the same logic: the current going out of the battery pack is measured - by a shunt inside the pack. that said, you need to connect an extender pack AFTER the battery pack - as the inverter does not care how many Amps it receives during a drive. The real issue is that once the weakest cell in the OEM battery reaches minimal voltage, you get turtle mode, even if you have a few more kilowatts in the extender pack - but range increase can be reached - similar way how Muxan made his first exender pack for his leaf - same logic.

Adding a second contactor for the extender pack ,as it is vital that both batteries are disconnected when ignition is off, otherwise the car is permanently paralized, and connecting the secodary pack to the inverter can be done in a net fashion, as the main contactor relays leads are under the back seat, and the inverter is on top of the motor under the trunk area - so all needed connections are close to each other.

Best regards for your new hobby tool. As you might notice by now, my car is also kind of a hobby for me - but so far i focus on the heating as here in Poland winter can be serious.

 

[drcat]

Hi,

if you are in search for a tiny but powerful generator, take a look at the 2nd gen GM eassist starter-generator, used in several cars like the Buick lacrosse hybrid (parts nr. 24261691 AA), mind you it has a rather tricky resolver.

As for the battery saga: the i-miev and the 2014 leaf works according to the same logic: the current going out of the battery pack is measured - by a shunt inside the pack. that said, you need to connect an extender pack AFTER the battery pack - as the inverter does not care how many Amps it receives during a drive. The real issue is that once the weakest cell in the OEM battery reaches minimal voltage, you get turtle mode, even if you have a few more kilowatts in the extender pack - but range increase can be reached - similar way how Muxan made his first exender pack for his leaf - same logic.

Adding a second contactor for the extender pack ,as it is vital that both batteries are disconnected when ignition is off, otherwise the car is permanently paralized, and connecting the secodary pack to the inverter can be done in a net fashion, as the main contactor relays leads are under the back seat, and the inverter is on top of the motor under the trunk area - so all needed connections are close to each other.

Best regards for your new hobby tool. As you might notice by now, my car is also kind of a hobby for me - but so far i focus on the heating as here in Poland winter can be serious.

last thing first
I'm 20km from Poland and it was Poland 70 years ago here and happy 3 Kings Day though Finally some snowy days
For the 2nd battery in trunk - its still a good idea and for the current measurement cheating
For the current spoofing, I think I saw a successful solution here https://li.energo-e.ru - basically that guy seems to be the only real entrepreneur in whole the Skolkovo / Moscow (others are just using zero import fees and reselling useless things from ali stating they've invented and producing those thus working as a money laundry ). So closer to the subject, he builds any custom batteries based on 16850 NMC and in one of his videos he elaborated much on current spoofing:
https://www.youtube.com/watch?v=mnIlnW3z0bg
unfortunately, in russian but basically what he did: reduced the resistance from 150 mOhm to 70. But leaf has two current measurement systems - one for charging and another one for discharging. I wonder if anyone knows if i-miev has the same schema. This elaborated here:
https://www.youtube.com/watch?v=vUi7NXhh-bE
Thus using this setup he had to disconnect 12V battery to get more capacity out of the battery (while there's no problem with charging to the full capacity).

And I would still like to spoof BMU output to CAN completely to throw out all the CMUs and BMU - that should be a cute jailbreak to put in 100KW handmade battery

 

[drcat]

drcat, congratulations on your purchase!

Before you do anything to/with the car, DRIVE IT! Get a feel for what works and what doesn't, and especially note how simply driving gently and slowing down has a dramatic effect on how far you can go. We have a saying around here: "Range is whatever you need it to be". Don't be put off by the the car's apparent range, especially now, as it drops significantly in winter. For example note, that when you turn ON the car's heater, your RR indicator will drop by 20%! Solution is to wear warm clothes and use the seat heater, as its consumption is negligible - the biggest issue you'll find is condensation on the windshield and if you read some of the posts about winter driving there are schemes to mitigate that.

Don't even think of a diesel REX - you own an electric car, not a hybrid! That said, on this forum you'll find a successful ICE 'pusher' solution by jray3 that worked, the only mod to the car being the addition of a trailer hitch.

There are many discussions on this forum regarding possibly upgrading or supplementing the battery pack. All were quite a few years ago when there wasn't anything else available and any mods required a LOT of time and energy and cost. Biggest stumbling block is what you pointed out: spoofing or circumventing the car's present communications.

I think that you might find that the i-MiEV's range, even with your 32Ah battery, is sufficient for most of your local driving needs. Again, become comfortable with the car the way it is presently configured before undertaking any mods - which is not to say that contemplating and researching is not to be discounted. Have fun!

Hey man, I'm driving it daily but I have no power outlet close to it to leave it charged tonight daily so I definitely want a bigger battery and I want to use it sometimes for driving ~350-400 km so I want a REX worst case.
As for heating - it gives me 55 instead of 80 km (~0C temperature) just when enabling it - sure thing, 5kW consumption till warmed up and ~3 when temperature needed reached. I would rather use a ceramic heater and a small fan so 500-600W would be enough to heat it with a hot air instead of warming up the whole system.

Thank you for directions sir!