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Discussion Starter #21
Go for it and see how you get on.
As I say document it on your own thread when you get going.
 

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Discussion Starter #23
Not much to show visually today.

Labelling the high current wires so less possibility of error when connecting to the LTO packs.
The four wires are now.

1) Red P (Pack main positive)
2) Black BN (Pack break negative)

3) Red BP (Pack break positive)
4) Black N (Pack main negative)

The first LTO block connects to 1 & 2
The second LTO block connects to 3 & 4

I have been analysing yesterday's data and am building a device to hopefully allow the car to accept a higher voltage pack without throwing codes.
I'll be adding a four connections to the IPU wiring to bring the signals I need to a more accessible location out from under that metal IPU cover etc.

I'll have a little test connector block and a bypass jumper to return things to stock if problems develop with the magic black box voodoo gadget.

I also need to find out if I can do the IMA rotor calibration with my HDS.
That will save me having to swap out my MCM and put it in this test pack, although I might do that anyway.

Lots of work still to do.
 

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Discussion Starter #26 (Edited)
I am using ex Honda FIT EV LTO 20ah cells for my prototype Nimh to Lithium CRZ conversion.
You of course can use whatever Lithium cells you want as long as they meet a few critical criteria.


These are a few guidelines and recommendations based on my long experience with Lithium, EV's and IMA conversions.

1) Use a safe Lithium chemistry. Not all Lithium batteries are naturally safe or rugged.
Don't be tempted to use LiPo unless you are an expert.
Yes they are powerful and light, but unless managed with a very good BMS they are flaky.
We have all seen pictures/videos of cheap scooters and the odd phone in flames.
Choose wisely and choose once. IMO Lifepo4 and Lto are good conversion candidates.

2) Don't underestimate the punishment and stress the car will inflict on cells.
The OEM Nimh cells are incredibly rugged, long lived and robust with a +100A assist and +50A charge capability.
It's remarkable they work as well as they do, but Panasonic really knew how to make them.

Any Lithium cells you choose must be at least on par if not better than the OEM cells as far as electrical properties are concerned.
Don't always believe exaggerated data sheet performance claims and numbers. Find some cells with real world hard data to back claims up.
If the cells you choose are at all marginal the car will punish you by killing them in a short time and possibly burning it down.

3) A BMS (Battery management system) is a tricky problem.
The LTO blocks luckily don't seem to need much managing/balancing, but other chemistries may need a lot.
I use my own systems to manage the LTO packs, you will have to research options very carefully.

Do not get any sort of BMS that has built in mosfets to cut power etc. This is common with cheap bike packs and the like.
They are fine for your scooter, but if any BMS cuts the main power directly you will get an immediate IMA fault and possibly damage the inverter.
Any BMS you get has to communicate with the car properly and allow the car to shut things down in it's own controlled way.

4) Don't underestimate the time, effort, skills and money it will take to do a conversion to Lithium.
Unless you have all the skills and parts already you will need fairly deep pockets to get everything required and then pay someone to do it.
Messing around with high voltage isn't cheap or easy, and a lithium conversion will never likely save you money in pure mpg terms.
Of course you will be able to follow my video guides and posts, but you still need all the other stuff above.

I bought a second pack so I could do the mods and research on the bench in advance of the actual fitting.
On my conversion day itself the process should be as quick as pulling out the old pack and putting in the new. Half a day maybe.
Once one conversion has been done and any bugs ironed out, then doing others will be much quicker.
Some enterprising people might offer a swap out service based on my work/ideas. ;)

5) Mods and OEM warranties do not go hand in hand. Honda are not going to fix your blown $3000 IMA if you mess up or it all goes wrong.
Do not undertake or get involved in any IMA modding except under the express understanding that you could break the car and lose your money.

6) Why do it then? Well if you like performance, the CRZ certainly does look sporty, and goes reasonably well.
But a lot of us crave a bit more oomph, or at least would like to be on par with our lucky OEM Lithium CRZ brethren.

IMA modding will give you significant bhp/torque performance gain and possibly some increase in mpg when the car is driven sensibly!
The OEM 10kw motor is easily capable of much higher outputs for short periods, 15, 20, even 30kw is doable with sufficient ingenuity and $$
30kw = 40bhp, that's a considerable leap, but the extra low down torque and acceleration is the real bonus.
Combined with some of the other popular CRZ mods like turbos and superchargers you will have a real beast on your hands.
The IMA will get you off the line and spinning up then the dino fuel can take over.

If I think of anything else i'll add it later/edit this post.
Thanks for your interest and feedback.

Peter UK

PS A few videos showing recent Insight G1 LTO accelerations runs and old rolling road testing.

No assist.

30kw assist.

Ten years ago on a rolling road running at 18kw in early IMA testing.. (Power graphs linked in the video description.)
 

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An extra 20bhp for a few seconds would be good.
I believe there should be scope to increase the output because starting the engine probably needs more current than when on the move.
It would be good to repurpose the decorative* S+ button to give the extra bhp.

* can't say I've noticed any benefit compared to sport mode.
 

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Discussion Starter #28
A couple of videos from a chap in the US who swapped out his IMA pack for another standard one.
Shows that basically the rear interior trim and air ducting has to come out.
It's a bit of a PITA job but in for a penny in for a pound..



I won't be reinstalling any trim or covers etc etc until it's all been confirmed as working.
There is some space at the rear of the battery area box so with careful work and carving out the interior of the old battery case etc I think you could get a 48 cell pack in that low down area.
I will have a look today and do some measurements for my temporary battery tray which I will probably lash down to the luggage anchor points somehow.

In the UK I might be looking to buy a rear cargo floor covering so I can cut holes in it. Anyone got one?
 

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Discussion Starter #29
I believe there should be scope to increase the output because starting the engine probably needs more current than when on the move.
Starting with the IMA uses about 30-40A or about 3-4kw for a couple of seconds max so well within the motor capabilities.
Full 10kw assist will pull around 100A from a standard voltage pack if not a bit more.
 

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Discussion Starter #30 (Edited)
A couple more videos before I go off out to buy some 28mm aluminium box section to make my simple battery frame.

You can actually fit 4 LTO blocks neatly in the boot space which would give an insane 230V nominal 30kw+ potential system... :devilish:

Although the IPU inverter might be able to stand the 230V+ the DC-DC may stop working long before that.
Then you have to install your own DC-DC with a higher voltage rating to cope.
I used a Meanwell PSU as my DC-DC in the 30kw Insight project when the OEM one stopped working at ~220V.

Practically speaking I suspect 3 blocks will be the limit to avoid DC-DC issues and fitting another unit.

62530


Video 6 final pack bench assembly.


Video 7 boot mounting options.

 

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Discussion Starter #31
I've changed my mind and decided to document this project on here in detail rather than on Insight central, and I have edited my original post to that effect.
It does make more sense to have it on this forum which seems to have a decent size membership.

However if you want to do some background reading on all the IMA developments over the years you will have to go there and do some digging.
Everything I'm applying to the CRZ had been developed, discussed and documented on IC over many years.
 

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@PeterPerkins have you dug into the connection/communication between the ECU and whichever IMA controller it talks to for the manual assist mod yet?
 

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Discussion Starter #34 (Edited)
@PeterPerkins have you dug into the connection/communication between the ECU and whichever IMA controller it talks to for the manual assist mod yet?
One thing at a time. ;)

I have sniffed the CRZ and HCH2 IMA CAN bus a few years ago and have some data from back then.
I haven't dug it out again yet, but assuming this initial Lithium conversion is successful it will be on the growing to do list.

You reminded me I need to add an IMA CAN Access point to the harness of the modified assembly waiting to go into the car.
Then I won't have to take it all out again to do it later. (That's another job for today!)

To modify the CAN signals for manual IMA control we will need a duplex MITM (Man in the middle device)
I have been working on one for some months and developments are in this thread over on IC.


Todays jobs!

1) Sleep & Eat.
2) Add IMA CAN Bus Access
3) Plug in Honda HDS and re-familiarise myself with its operation. (Can I do the rotor calibration etc)
4) Build LTO battery bracket support and test mount in car. (I now have some 16 SWG Aluminium box section)
5) Book local rolling road for simple baseline power run Monday with stock setup before it gets changed later next week.
6) Draw up schematic for the magic voltage box..
7) Do some Insight work..
 

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Presumably you'll need to intercept the CAN data and forward it with the relevant data modified. I made a vnt actuator controller for Holset and Hella CAN actuators a few years ago. As it was standalone, I didn't have to modify the data, just transmit it. It took a while to get my head round it using an AT90CAN64 and MCP2551 transceiver. (I'm not a programmer so was thankful for Bascom)
A Microchip CANBUS analyser was a godsend.
 

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Discussion Starter #36
The 500kbps CRZ IMA CAN bus IIRC is bidirectional so you have to pass stuff (data and acknowledgements etc) through in both directions.
Your device in the middle has to deal with this at a very high rate and selectively modify the packets you want.
It also has to interact with whatever your control mechanism is joystick, buttons etc etc.

We also have to capture and reverse engineer the current data packets/traffic to work out what needs modifying etc.
It's not an easy project. Save that for another thread or start one if you wish.

Edit.. There is an old thread on here (started by me) about this and there may be others.

 

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Discussion Starter #37 (Edited)
Rolling road baseline power run booked for 1pm Monday. (System will be untouched for this)

Added IMA CAN bus access wires to loom for data gathering etc later.

Made up simple LTO Lithium 3 pack mounting using 28mm 16 AWG aluminium box section.
For testing this will secure to the child seat anchor points behind the rear seats using ratchet straps.
Initially the centre block (or one of the others) will be removed to leave two packs for the 48 Cell OEM voltage setup.

 

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Discussion Starter #38 (Edited)
Delving into the HDS Diagnostic system plugged into my CRZ I saved the following list of available info for the IMA and PGMFI systems on my car.
See pdf files attached. I noted my car is the SPORT-T version 124PS.

The IMA Battery useable capacity was 34% which seems low, and probably why I think it feels feeble compared to my Insights.
The 34% figure above is not the current SOC which was 64%.

My understanding is that the maximum useable capacity of the pack is about 3.5h between 20 and 80% SOC on 5.75ah cells when new.
So 34% of 3.5h useable is left now after 73,000 miles, which equals 1.20ah which seems pretty crummy.
I suspect a lot of NIMH packs out in the wild are weak but keep on going albeit down in the performance doldrums.

The pack voltage was 112V resting with the DC-DC off and the engine stopped.
It seems I will be able to perform the MCM motor calibration so can swap the complete pack out.

There is also a menu item to delete the battery history when swapping packs.
This probably resets the useable capacity % back to the maximum. ;)

There is also a SOC setting (low, medium, high) which may well be required to fully utilise the capacity of larger Lithium packs.
I had to do this on the Civic HCH1 and we just kept setting the SOC to high until the Lithium pack was actually exhausted.
That worked fine.

I also found this pdf of testing a 2011 CRZ Nimh pack by Idaho national Laboratory.
 

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Interesting stuff. I should have my hds working when the replacement cd arrives so it will be interesting to see what it reports for my Lithium batteries.
Can't say I am surprised at the loss of capacity - NiMh batteries were always known to lose it over time.
I will refer the member who has no regen charging to the IMA pdf as his workshops should be checking his IMA data.

I came across some threads elsewhere about Honda doing an IMA update after too many warranty claims for the IMA battery. It sounded like they had fudged it to make the SOC gauge not reflect the true charge level - i.e. read high to keep owners happy and keep them away from the dealers. "my IMA is hardly doing anything" - "the SOC gauge is reading okay and there are no DTCs' so nothing is wrong..."
 
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