Having been delving around this a bit recently and studying the manual I think we might have another option for more power with a Lithium upgrade.
The HCH1 IMA current as we know can be increased tweaking a number of current sensors for an 18.5% increase. Matt says this works well on his car and he is using the stock 100A fuse.
However increased system voltage can also deliver more power without increasing current and abusing the 100A fuse.
The IMA power in Watts is simply Amps x Volts.
If the system voltage under load is 140V x 50A that gives 7.0kw
If the system voltage under load is 180V x 50A that gives 9.0kw
The HCH1 MCM detects the system voltage using the battery voltage tap inputs.
It does not
appear to have a second voltage check from the IGBT/driver module like the G1 Insight does
Looks like I was wrong about this.
The G1 Insight uses voltage taps for the BCM voltage detection, but this is compared with a special voltage check analog signal that the IGBT sends to the MCM. These two values are compared by the MCM, and so both had to be faked to enable a voltage hack mode in the G1 Insight. Quite difficult and a bit of a PITA.
With the HCH1 it appears
only to have one voltage sensing system (via the taps), which is faked in my Lithium pack by the BCM fooler resistor matrix, and made adjustable with the addition of the pot on the + end to fake a lower system voltage if reqd.
I may simply be able to turn the detected system voltage up and down with the simple pot and the actual battery voltage will determine the IMA power. We already know the car tries to compensate for an apparently lower system voltage by increasing IMA current so we get a double bonus
Only a test will determine if some other voltage detection is being implemented but from study of the data and the IGBT data sheet etc I don't see anything. Fingers crossed!
PS I saw 90A briefly from my stock HCH1 setup today as battery temp was 25c or so. So I might simply fake the oem NTC battery thermistors for a static 30C battery temp to ensure the IMA will deliver full current with my Lithium setup. I need to take some measurements of their resistance at 25-30C or so.