My 2012 imiev recently had its OBC fail in the middle of a charge cycle. (35K miles) The aux battery was in good condition and the car was charging in a cool garage. I live far from a Mitsubishi dealer (Upper Peninsula of Michigan) so I decided to try and fix the problem myself. The car was back on the road in 9 days.
Here is what I did:
1) Removed the entire assembly that houses OBC. Covered all open connectors with shrink wrap covers.
2) Rerouted the cooling hoses to account for the dcdc converter charger box being gone.
3) Replaced fuse in the inverter box with a 400vdc 4amp fuse
4) Used the carsoft i909 to clear the error codes on the ev ecu.
5) Plasma cut an 1/8 aluminum plate to mount the coolant tank and a brand new HLG-600H-15A from Meanwell. This power supply is meant to drive LED lights, it has adjustable voltage and current pots built in with a remote and 5V output line, and has a 431 VDC input limit.
6) Wired up the high voltage DC from the inverter box to the input of the mean well power supply, put an arduino micro controller on the 5v line to trigger the remote line a second after the supply gets input voltage. (otherwise the car will trip an error code during start up) The output of the power supply is set to 14 volts (after the diode) and routed though a high power diode which is affixed to the aluminum plate with thermal paste.
7) The expensive part (but worthwhile, I can charge the miev at 7.2 kw now) I bought a chademo charger from evseadapters.com, I use that since I no longer have an on board charger. Takes about an hour to go from 20% to 80%.
A couple notes: with the high beams on and the hvac fan on high, when the brake booster pump kicks on I can draw more current than the power supply can manage, so my voltage will dip into the 12.7 range for a few seconds. So far it has not been an issue, I just use a voltmeter in the 12v power jack to keep an eye on things. The red battery indicator light will stay lit on the dash since the car thinks it has no DC DC converter- I took apart the dash and put electrical tape over the back side of the overlay.
3700$ total into this endeavor, but I got the car 4 years ago for 5900 and its been a real treat to drive so it was not hard to justify. Link to the charger:https://www.evseadapters.com/collection ... ck-charger
Here are some pictures of the fix and the fancy new charger:https://drive.google.com/drive/folders/ ... sp=sharing
Response to some very good questions about this mod:
1) The setec charger takes the car to 80%, you need to restart the charger manually to charge to 95% (See comment 6)
2) Cell balancing does appear to be taking place, I have 4.10 volts across the board according to canion when I charge to 95%
3) I also bought the J1772 EVSE to nema 14-50 outlet from evseadapters.com to use at public charging stations, though I mainly charge at home. I can route the cables through the rear window so the charger stays inside the car if its rainy or snowing.
4) The meanwell power supply is completely sealed except for the access ports for the pots only have a rubber plug in them.
5) I thought about using the Elcon PFC2500 Charger, and at less than 800 bucks that would have been cheaper. I still think I would have gone this route if I had more time and skill.
6) The charger does cut off at 5 amps, or about 95% SOC. All cells appear to be balanced, will update if this is no longer the case in a few years.