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BTW, i was doing some math.
For 10kW of power at 100 Volts you need 100 Amps.
Which means if you will have 100Ah/100V battery, you can deliver that power for one hour.
For one minute at 10kW you consume 1.66 Ah, so if the capacity of the pack is lets say 5Ah at 100A draw, you can deliver it for 3 minutes.
Which is clearly not the way how the system works - the 2013 model allows boost for 10 seconds only.
It is clear why, 100A draw is 20C draw for 5Ah battery, which is high for NiMH and mild-to-high for LiOn chemistry.
If the battery would be abused that way, it would not last more then hundreds of cycles and 1-3 years.

So, my point is, the number of bars you see on the dash have nothing to do with the actual state of charge of the pack.
The electronics probably use roughly 20% of the capacity and only when the pack is in optimal condition, avoiding undercharging, overcharging, long term amp draw and temperature rise from the draw.
There is probably space to hack the electronics to behave differently, because this is too "conservative". :)
 

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Discussion Starter #42
@rygar

Yes, I was referring to 2013's Li-Ion battery pack capacity in Ah's.

If you are referring to balancing the IMA vs. 12V stock battery, according to the 2011-2012 block diagram (see Post #17) the contactor appears to disconnect the dc-dc converter when the key is in off position.

I connected my system ahead of the contactor, so balancing the IMA battery and my system occurs regardless of key position... but now that you mention it, rather than add a relay, all I would have to do is change my positive connection to the one indicated in the fifth photo in Post #17 showing where I made the negative connection.


@jointer

I'll connect a voltmeter when I get a chance.. but that probably won't be until mid-November at the earliest. Heading out of state tomorrow for work and will likely be away from home until then.
 

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Discussion Starter #43
...

So, my point is, the number of bars you see on the dash have nothing to do with the actual state of charge of the pack.

...
I agree somewhat. The number of bars is definitely not an indication of overall battery charge. That is, zero bars does not mean the battery is dead. Not certain exactly what it indicates, but I'd say it likely indicates it cannot deliver full horsepower to the motor in an otherwise normal assist condition. I notice that when I have zero bars when first starting and driving the car, it will not go into assist mode. However, there have been instances where when first starting the car there may be four or five bars showing, which then reduce to zero and the assist mode will engage on demand shortly thereafter.
 

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The service manual has a page or two about the battery charge. The charge indicator on the cluster simply references the SoC of the battery, not any potential to assist or not. That being said, you're correct that zero bars does not mean a completely empty battery. I believe the charge indicator shows zero bars around 20-30% true SoC and full bars around 80%. It can be demonstrated by still being able to charge at full bars. As you mentioned before this is simply for the health of the battery. There are differences between NiCd and Li batteries but this principle could apply to both of them, right?

Also from the manual: assist and charge intensity is dependent on temperature of the battery and electronics. There may be other factors, I'm not sure. I don't have access to the service manual at the moment so I can't cite anything but the manual has a couple graphs comparing SoC to bars in the charge indicator in addition to assist/charge vs temperature. Again this is for the 2011-12 electrical system.

Edit: Service manual pages 12-54 and 12-55 have SoC range and temperature effect information.
 

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I discovered CRZ two days ago, so after some googling, i found Honda Insight have this system too and over time, clever people found a way how to hack the system to provide +44% power to the motor and some even replaced the stock cells with LiFeYPO4 cells.
Complete manual control system was developed, see here:
Manual IMA Control HCH1 IMAC&C - CleanMPG Forums
There is youtube video, showing how the car can drive on almost only electric power for 20 minutes.

The CRZ system is more advanced, but i found somewhere that someone from UK is looking into it and is probably very similar to system in new Insight.

That is bit off topic though, we will see what is the long term experience of jhren, of the electronics is confused by the tap or can deal with it.
I had an idea of adding LiFeYPO4 cells in parallel, so the car would use the IMA more often.
Anyway, i will try to arrange test drive for next week, this thing really got my attention. :)
 

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Discussion Starter #47
Update

To keep interested parties in the know, here's an update on my installed-system performance.

After initial installation, I noticed the battery level (according to instrument panel indication) upon starting my Z after sitting overnight was substantially lower than prior to installation. Upon starting indication was fairly good but rapidly decreased to one or zero bar after a few seconds. The battery level seemed to come up fairly quick as I drove. But as noted in previous post, assist mode did not engage until there was at least one bar showing. As mentioned previously, I believe this a result of the add-on 12V system being a parasitic load on the Li-ion battery pack.

Recently I have been getting messages on start up to check charging system and to continue driving to charge the battery. I think this is an added effect of colder weather setting in.

Given this theory, I decided to connect the positive lead to the terminal beside where I connected the negative, putting the add-on system on the load side of the internal contactors. Note the plural use of "contactors". According to 2011-12 manual, there is a high voltage contactor and a bypass contactor with a series resistor in parallel, and also a current sensor prior to connection to the built-in DC-DC converter and where I made the connection.

After changing the connection, the 12V starter kicked in to start the car and I got a lit IMA indicator plus message(s) about the IMA system. I don't recall exactly whether it was one or more messages or the text of the message(s). I immediately checked the voltage at the fuses (I had already closed everything back up so this was the only point immediately accessible). I measured approximately 40VDC. Not good considering it should be up around 144VDC nominally.

I'm thinking the IMA "brain" calculates current in addition to measuring via the current sensor, and shuts down the high voltage contactor if there is a disparity... leaving the bypass contactor and resistor connected. This would explain the lower voltage... voltage drop across the resistor and the amount of current drawn by the add-on system.

For the time being, I have pulled the fuses and no messages on start up. The IMA indicator went dark after a couple starts. The check engine symbol did light up (not sure whether before or after IMA indicator went dark), but it too went dark after a few more starts.

I'm currently planning on reconnecting to the full time positive I formerly had the system connected to, but I'm going to add a relay after the fuses to disconnect when audio/media system is off. Because I cut the positive lead and split loom tubing shorter to make the connection, I'm going to redo the leads completely. Already have a relay, but rather than using red loom tubing this time, I found 10' orange loom tubing available for purchase (opposed to ordering 100') and waiting on it to get delivered at the moment...
 

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Discussion Starter #48
Update

Been a week now since I redid my 144V leads as originally connected and inserted a 12Vdc-controlled DPDT (double pole, double throw) relay after the fuses. All is operating well. Battery indicator shows the IMA battery pack retains charge while key is off (up to 2 days of not being driven so far). Also, because I used a DPDT, I added a 120Vac cord to the NC (normally closed) contacts so I can plug into 120Vac power and charge my add-on system.

:headbang::thumbsup:
 

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Keep us informed.
I test drove the car, found it to be less powerful then expected (2012 model) and also with too small trunk for my needs. :(
And the 3D speedometer was not comfortable for me.
But i am still interested in your experience.
Do i understand correctly that you are able to charge the batteries from AC?
Or only run the audio from 120V AC?
 

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Discussion Starter #50
The 2013 model has more power. I've never driven an earlier model, so I can't make a comparison. Just going by published numbers. Not saying your going experience G-forces in excess... but its okay for normal to somewhat aggressive driving.

Trunk space is limited. The retractable cargo cover is easily removable and I replaced the cargo divider and forward storage tray with a custom built-in band-pass sub enclosure... and only lost a little space compared to the cargo divider folded down. Still more than enough for my common needs. Only time it's restrictive is when I pack up for going to work away from home and coming back... but I manage.

The speedometer isn't really 3D. It's simply a reflected display. Getting used to a digital speedometer takes a little time, having only analog for many years in previous vehicles.

After re-configuring my add-on system, I can now plug it into household AC and charge the auxiliary 12V batteries. That is, if need be (that occasion has yet to occur), and only when the car is parked and the media* system is not powered up.

* Kenwood DNN990HD head unit.
 

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Everything still working fine?
Off topic: I bought used CTR 2010, not everything is in good shape, but suits my needs surprisingly well, especially the cargo space. And the power is also nice. :)
 

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Hey there jhren I know your DC DC post was from 2 years ago but do you have any more information on this project. I am looking for a converter not sure which one. Running three thousand watts rough. Do I need the converter and DC DC ? Any help would be greatly appreciated
 

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Discussion Starter #54
Sfsafepassage

Sorry I missed your post. I have notification turned on and I got notified of Rorence post so I do not know what happened. Anyway, I assume you did not wait this long for me to reply so how did you manage?
 

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Alright JHREN I'm bout to do a serious setup of 2 different amps. A 6 channel 800 watt for my components and a '2500' WRMS amp for my sub. It really puts out about 3k but anyways I need to know what converter and relay you used so I can do the same thing. I also have a 2013 Honda CRZ. I was going to run off my 12 volt battery with an extra battery, but I'll end up clipping the amps if I'm not careful. Could you tell me the brand and possibly send a link of what you used. It's so hard to find info online about all this stuff. Thank you for your thread and your relay worked like it was suppose to correct?
 

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Hello...!!!

New owner, new member here. Been lurking here a few days mostly on performance subjects.

In particular for this post, I plan to "upgrade" the sound system. The factory system is among, if not the best I've heard, as far as factory systems go that is... but still subpar by my standards.

I have a few threads regarding max continuous power available to the 12V system. 22.5 or even 30 amps will just not get it for my tastes... and I don't need any jargon about music being dynamic power. WRMS power is WRMS power. Though technically the term is jargon in itself, it does represent a method of "averaging" the dynamic power of a suond system. A max of 30 amps at 12V equates to 360 WRMS, period. I'm designing my sound system as efficient in the watts to decibels department as I possibly can. But currently estimating I'll need more than 360 WRMS.

The discussion in the other threads I've read seem mostly based on what amounts to replacing the factory 12V battery with one having greater surge capacity (such as an Optima or Kinetic battery). FWIW, that only works for the short term...

I travel in my profession, i.e. 500+ miles one way to get to the job sites. Once there, I only commute until the job is done... then perhaps another 500+ miles back to the homestead. While I'll likely not be jamming at max decibels the entire trip, I can foresee discharging (to a degree) any battery on the long hauls. While heat is the number one destructive factor of electronics, undervoltage exacerbates the effect. Ultimately, I need to find a way to get more juice...!!!

So getting down to the nitty gritty, it currently amounts I cannot install (though I've not investigated the possibility of adding) an alternator with greater output... cuz' the Z has none. As I understand it, the 12V charging system relies on a DC-to-DC converter (i.e. volts to volts) and is the limiting factor. However, can easily be likened to and underrated alternator on non-hybrid cars.

So what do we do in that case? Generally two options or a combo thereof, and that is to get a beefier alternator, and/or install a second, or third (or fourth in extreme cases, given there's enough room... :)) BTW, I have a full size chevy express conversion with a 11,000 WRMS A/V system and a single underrated 300A alternator, but two to five Kinetic 3800 batteries depending on whether I'm in competition mode or not :) ... so I do know what I'm talking about here.

Anyway, I'm currently seeking information on the DC2DC converter. Exactly where is it located? (pic's???) Exactly what is it called by Honda? ...or its part number? How was the 30A figure determined? Has anyone considered, looked into, or actually paralleled two or more of them?
I have a lincoln mkz hybrid and I'm interested in doing what you talked about here. Its been 7 years. Just wondered if you had any long term issues.
 
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