Enginer PHEV kit Rebuilt with quality components and new batteries

Ok. So after another 8 hour day it's finally finished and working well so far.

I won't have access to my pc or Internet other than my phone for the next 2 days, so I won't be able to upload the pictures for a few days.

We ended up ditching the contactor.
Went and picked up a mini latching relay from the local electronics supplier.

Vincent quickly hooked it up inside the BMS case
And we used that to drive the 2 pin connector from the enginer DC-DC and it works like a champ.

It is definitely a NO type connection.
In NO the DC-DC will turn on. If this is closed / shorted, it turns the DC-DC off.

The red light up front still comes on if I have a LVC or the BMS trips for any reason.

The next few days will tell me just how well it performs.

I will post pictures as soon as I can with a fuller description of the remainder of the install.


But I'm happy with the result of the 2 days.
Still some very minor tidying up to do, and get a carpet to cover it all.

Jason.

 

For the bms I am using, if there is a LVC trip, I have to manually reset it.
It will not allow further discharge or charge until the bms has been reset.
However, if I turn the DC-DC off when I hear the beeper from the bms,
I will not have to reset it. The bms will sound the alarm for 30 seconds, before it trips.
So I should have plenty of time to manually switch off the kit.

Also, I think we have one small issue with the install....

With the charger plugged in and charging, the SOC meter goes down ? Not up !

I think we may have placed the shunt the wrong way around.
Should be fairly easy to check and rectify.

Other than that, it does seem to be working well.
I let it run for a few minutes to see if the amps would fall away as the HV voltage rose, and they do. At about 70% charged, the DC-DC throttles back to around 6-7A then lower as the HV battery rises.

That was one concern that I had.

So, now all I really need is to sort the charger issue and I'm good to go.

Once again, I'll post the pictures from today when I can get back to my home PC.

Jason.

 

ok, im back home now

here come the pictures....

so, Day two begins with bolting the cells together and installing the cell modules...



here you can see all of the interconnects and cell modules installed.
note that at this stage, the 2 sides of the pack are NOT connected.
the link at the far right side is NOT connected. this was done for safety reasons, so there is less chance of shorting anything and also less chance of a shock should you accidentally touch both side of the pack at the same time....

you can also see the soldering iron at the ready for the next stage...

all of the cell interconnects are soldered together in series, with a 100ma fuse in the center of them. this is the signal line that the cell modules use to communicate with the BMS. (the thin yellow wire)




the BMS turned on for the first time
here you can see the SOC meter... this will be relocated up the front near the driver at a later date.




here you can see the mini latching relay that was used to replace the contactor.
note the size difference !



the contactor would have worked, but then i would have needed to use a automatic precharge circuit of some kind.
as we tested the inrush current of the DC-DC converter, and it was significant. too much for the long term life of the contactor.

so we decided to investigate further the use of the 2 wire control from the DC-DC converter.
we went to the local electronics retailer (jaycar) and bought the small latching relay.
Vincent was able to disconnect the latching contactor from the BMS and wire in the mini relay, but in the opposite connections to the original contactor.

the contactor was supposed to be closed when the BMS was on and happy, and open when the BMS is off or tripped.
we needed the opposite behavior. the mini relay would need to be open when the BMS was happy, and closed when it was not happy.

with that sorted, we tested the operation of the BMS and by simulating a low cell (by disconnecting the cell module line) the BMS started beeping, and 30 seconds later, it shut off the DC-DC converter and the red light on the enginer switch came on.

we also tested what would happen if the BMS was turned off while in operation. in this case, the relay also closes and the red light on the enginer switch illuminates.

the downside to this control method is that there is ALWAYS SOME draw on the pack even when the system is off.
this is very minor. it's only the leakage current required to keep the large capacitors inside the converter topped up.

this is exactly the same method as the enginer BMS used. it had no pre charge circuit, as the caps were always energized.

so if the system is not going to be used for a month, it will need to be plugged in for a few hours.
the alternative is to flip the 100A breaker on the side of the box, as this will also shut off the entire system completely, but then there would be a very large spark inside the breaker when turning it back on (ask me how i know this ?)

here you can see the 4.5mm sheet of clear polycarbonate that was used to stop any potential contact between cells and the lid of the box...




here we are getting ready to hoist the box into the car...





here you can see the box in mid air suspended by the hoist. we were testing the charger and whether the BMS would control the charger as it was supposed to. we also had a clamping type meter on the output to the battery pack. it was charging at the full 25A as expected...

we also tested the charger by turning off the BMS to see if it would shut the charger off (it does) and we also tested the cell module line again, to make sure it would shut off the charger if the line went open (ie a cell was over or under charged) with the line disconnected, simulating the over / under charged condition, the BMS complains loudly with beeping for 30 seconds, then kills the charger. good, it works.




here Vincent is tapping into the AC line into the charger to power the cage fan that we bolted to the charger.




here it is lowered into place in the trunk.




all bolted in and buttoned up.


the bolts that protrude through the top of the box are part of the new battery hold down system.
the threads will be cut back at a later time, and a suitable piece of carpet will be used to cover it all up.
the new box height is about 70mm or so higher than it was before, so the original floor piece will no longer fit.

temporary home for the SOC meter. ill move this later, up front somewhere.




plugged into a watt meter and charging nicely. drawing 6.6A at 240v.




so, i guess the next week or so will tell me how well it is performing.
i don't expect any problems though....

hopefully this thread will be useful for other enginer phev kit owners in future.

i will keep this updated if any problems arise.

i have also completed the first full charge / discharge cycle.
i got about 2 hrs of highway use from it before the BMS started beeping and i shut the system off before the LVC tripped.

it kept the HV battery at or about 75% for those 2 hours. for the entire 3hr trip, i had the AC running also. it was nearly 40c here today....

the charger has just now shut off after 4 hours, showing just on 6kwh drawn from the wall, which seems a little high.... i will have to investigate what's happening there.... i was expecting about 5wkh, maybe 4.7 - 5kwh, but 6 seems a bit much....

i will get a chance to test it out tomorrow at town speeds and see how it performs.

Jason.

 

thanks.

i donated the old gear to the person that helped with the install of this new pack / charger / bms.
4kwh is plenty for my daily needs also.

Jason.

 

just got home from the first city drive with the kit installed and running.

i have 579km on this tank, of that only about 180km have been with the kit running.
before plugging in the kit again, this tank was averaging 4.9L / 100 km, which is about right for my car.

with the kit turned back on, this has dropped all the way down to 4.3L / 100km ! in only that last 180km...

the first city drive involved about 30km loop out to get some shopping, and a few errands i had to do.
all of it in 50-70km/h zones. just kept up with the traffic flow. averaged below 2.5L / 100km for this trip.
that's about 1/2 of what it would have been with the kit not running.

happy days.
in that 30km i used about 30% of the pack too. given that my daily work commute is only 35km, i should be able to get 2 days out of it before recharging is needed.



please excuse the over exposed phone picture, and the dirty MFD...
also, note the outside temperature... today is a good 6c COOLER than yesterday....

Jason.

 

i wanted to post an update after my first full week of commuting and a few short trips here and there...

so the numbers are in, and those numbers are nothing short of FANTASTIC

the first week was about 270km (to and from work mainly in 70kmh zones)
the week ended with 2.5L / 100km average (94 mpg us) and consumed 17.82kwh from the wall to offset the fuel used.

still showing a full row of bars on the fuel gauge.

as a reference, the 2.5L / 100 is as displayed on the MFD and in my car, the MFD seems remarkably accurate.
guess i will see the real numbers when i fill up in 3 or 4 weeks time.

EDIT: lost the first bar from the fuel gauge at 297km.

Jason.

 

thanks.

some great numbers there.
my daily commute is only 35km round trip. and im finding that i am using about 3.5kwh a day from the wall.

roughly 75-85% per day. its been said that the batteries i used are more likely to have 44ah or so useable.

they are rated for 40ah, and i don't intend to push them very hard.
at maximum load they are only seeing 1C discharge rates.

i have now completed the 2nd week. still averaging 2.5L\100km on this tank.
i now have a shade over 410km on the tank, and still showing all but one fuel bars on the gauge.

it's good to know that others are rebuilding these kits.
when they are working as originally intended, they are great.

Jason.

 

yeah, i have seen up to 75A load at the pack.
but that was measured using the old enginer BMS monitor though, so the reading may have been unreliable ?

even at 1C, im still good with these cells. they are rated up to 3C.
so at 1C im not pushing them hard. output on my DC-DC is up to around 14A or so.
measured with a SG2.

i will have an opportunity in the next two weeks or so to open the battery box and then i will grab a clamp on meter and measure the load with a known good measurement tool.

as a quick update on the economy im getting...
im seeing 2.5L per 100km with brief drops to 2.4L / 100km this tank so far.
i have 640km on the tank and still showing 2/3 full.

Jason.