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Discussion Starter #1
Hi folks,

Has anyone modded their Insight to recharge the IMA battery while parked in the garage?

Seems for a few penny's worth of electricity, I could start each day with a fresh, full IMA battery. When my battery is full I get great mileage. After running around on a hot day and using boost a lot, I sometimes wind up with only 1/2 to 1/4 charge left when I get home which just reduces mileage further the next time I drive the car. Would be real nice to top-off that battery via an external power source and I can't imagine it'd take much electricity, given the relatively small size of the pack (compared to a pure EV).
 

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yes it has been and is being done.

if you want the SOC in the system to keep track of it you have to have the key on in the accessory possition.... and you must be !!!EXTREAMLY!!! careful when you connect the deadly / leathal volatge connection... do not do this is you are not well exterienced and know how to deal with nearly 200VDC.... this is a job for qualified experienced educated personel only... the high voltage battery in the Insight can easily kill you.

If i recall correctly someone was doing this without the SOC being kept track of ... ie, they had the key out of the ignition and the accessory power was off... which was causing some issues but was working in limited ways... I do not recall all the details.... search around the forum and such you might find it .... I seem to recall mike at http://www.99mpg.com was working with someone on this but again I do not recall all of the details off hand... ... search around ... or email mike would be my advice...

but the short answer is yes... have been done .... can be done...
 

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Discussion Starter #3
Thank you for the response. I know how to deal with high DC & AC voltages, so not a worry there. I can leave the key on, I keep the car in a locked garage.

So, is Mike the only one doing this, or have others done it different ways and are there instructions or a how-to floating around? I did poke around at 99mpg.com and it looks like this can be included with MIMA but I'm concerned about MIMA voiding my IMA warranty, at this point I'd prefer to just have a basic external charging ability and nothing more.

(I hope I'm not straying into banned territory here - not trying to start a MIMA discussion - just want to know if external charging is available any other way. If this discussion is inappropriate per the rules I apologize.)
 

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EVFan said:
...it looks like this can be included with MIMA but I'm concerned about MIMA voiding my IMA warranty, at this point I'd prefer to just have a basic external charging ability and nothing more.
And you are not concerned about external charging voiding your IMA warranty. :roll:

JoeCVT - Just your average CVT owner
 

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The technology of the Insight battery pack does not allow charge determination by voltage. Recharging the pack without knowing the status of the battery charge will likely lead to overcharge and recalibrations (recals). Neither will destroy the pack immediately, but the overcharge condition will increase electrolyte venting from the cells and the cycling caused by recals will gradually degrade the coiled cell electrodes. That said, if your warranty is expired and you want to experiment, you may be able to set up a timed charge system similar to what is used on many simple consumer chargers. If you monitor the recharge using the SOC meter in the Insight you should be able to characterize the time required for various indicated charge levels.

Another approach would be to use a deep cycle large capacity battery to store the power you will need to provide the Insights 12 volt energy for the duration of a regular day. The extra battery would be set up in parallel with the charging system in such a way that the Insight's charging system will kick in if the voltage falls excessively. This system could provide as much cheap energy as the IMA charge mod, and would avoid dealing with potentially lethal IMA power.

Note that Toyota is currently seeking legislation that will clearly exempt them from responsibility for damage caused by modification of their Synergy system. If enough owners hack their systems Honda will likely do the same, therefore neither myself nor anyone associated with this site recommend either mod. Expecting Honda to honor the IMA warranty when the pack is being stressed by the customer is unreasonable.
 

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Discussion Starter #6
Joe: Yes, I'm sure external charging would void the warranty if they found out, too. I simply figured that could be disconnected with 10 seconds effort and nobody would ever know, vs the time it would take to remove MIMA.

Kip: I appreciate your reply as well. I agree that stressing the pack and asking for warranty coverage is unreasonable. It was not my intention to stress or overcharge the pack in an inappropriate manner. I was looking for a way to provide the power through the IMA system so it could charge the pack and track SOC, thus ensuring all of the battery management systems Honda built into the vehicle were doing their job.

Anyway, I have enough info to move forward now (or make a decision to not). Thanks to all for your replies.
 

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EVFan said:
So, is Mike the only one doing this, or have others done it different ways and are there instructions or a how-to floating around?
Mike is not the only one... but his web site has the best description with pictures of how his v-boost system attaches and works... of course his v-boost does it while the car is driving, with a battery pack ... but the same method can be used without the batteries at home while the stock IMA control system is all powered up to keep track of the SOC.

I forget his name but someone else who has an insight has a high voltage input power supply they are using less than 1 amp charging current to charge up the stock High voltage battery.

The basic idea is that the stock system will keep track of the SOC and current in and out if you feed the stock high voltage battery at the correct point the correct DC voltage while the car is turned on.... Mike does this on the road with his V-boost system , and there are others who have rigged up smaller house power supplies to do it just at home....

You do not need MIMA to do this .... if all you want to do if top off the stock high voltage battery .... but you will be voiding your warranty just as much as previously said... Actually MIMA has nothing to do with the v-boost system he uses , MIMA is just a way to use the extra SOC.... v-boost just puts the extra SOC into the battery.

You might want to install the DC keep alive that other Insight owners developed / designed for FAS users to keep the Insights DC to DC working.... that way while you are parked you do not drain the 12 Volt system.... of course the DC keep alive will also void your warranty.... or you could just also attach a 12 volt mender / charger to keep the 12 volt system toped up while parked and having all the vehicle systems on....
 

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A small charger on the 12 volt battery would be a very simple way of keeping the battery charged and would require minimal wattage.
 

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Discussion Starter #9
Wait - so, if I simply hook up a regular 12 volt charger to the 12 volt battery, then turn the key on, the Insight will take that power and charge the high voltage pack? That seems entirely too easy.
 

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Correct, that is way too easy. It will only keep the 12 volt battery from being discharged by the IMA electronics that you are using to monitor the IMA battery charge. That charging will have to be done by an appropriate high voltage applied properly to the correct place. We really can not explain this further on this forum. This is a warranty buster and a potentially dangerous or fatal mod. Although I'm a technologist with decades of power conversion design experience, I have not considered doing this. If you need further help, please communicate directly with a member who has.
 

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Hi EVfan,
do a search for "grid charge" and you can find some old discussions on the topic. I've been using my charger daily for over a year now.
 

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The key to Armin's approach is to limit the charge current to a level that will not damage the cells even if you reach 100% SOC.
I believe he used 300MA as the constant current.
NIMH cells will convert overcharge to heat, which will cause the internal pressures to raise as Kip explained, until the cell vents, which is where the damage occurs. Theoretically the 300MA or less current should not generate enough pressure or heat on to damage the cells.

On my system, I charge the 48V lead acid pack, which charges the IMA pack only while powered up through the boost system, so my SOC guage is always reflecting this.
As Ian and I gain more experience with the packs, we should be able to better answer some of these questions.
Between his car, my car, and the Insight on a stand and the Silver Insight, we have 4 packs to compare and test.
Ian has driven the silver pack over 1000 miles and it is behaving perfectly after his cycling of each subpack. This is a 150K pack.

NIMH does have a memory effect issue, it is not as bad as NICD, but it is fully documented and real. Toyota actually has a full battery cycle built into their battery management software, to erase any memory, and it is part of their battery control patent.
Honda does not seem to have an equivalent cycle in their battery management .
My opinion is that it is better to use the pack throughout the full range. My car is going on 120K, and I cycle the pack fully several times during a 50 mile trip. Have not had even one recal.
;)
 

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Discussion Starter #15
That's good info on cycling the pack, Mike. I'll have to remember to do that once in awhile.

Plug-in recharging has become a virtually non-issue for me now. When I started this thread, I didn't realize I had a pack on it's last legs. I'd just bought my Insight and knew the pack was fairly small, so it didn't surprise me that it drained so quickly. I was still very happy with the car's performance and was averaging 60-70mpg consistently and up to 96mpg on certain legs of my commute.

Then my IMA and Check Engine lights came on and Honda replaced the pack, the main computer, and several other little pieces free of charge. With my new pack, I've only see it get near half power once. Most of the time it's one or two bars from full. My mileage has improved significantly, too (though I don't necessarily attribute this all to the new pack - I think a majority of it is just me improving on my ability to drive the car). My last fill up was about 180 miles ago. I've averaged 77mpg. The last 60 miles of that 180, I've averaged 84mpg.

I'm extremely impressed with this little car.
 

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A pack that had 150K on it was badly unbalanced when we pulled it. Ian ran each subpack through a few full cycles and was able to rebalance the pack.

It is too soon to see if the effect is permanent, but it is probably worth the effort to try it before just giving up on your pack.
I saw a prius the other day that had 330K on the batteries and they are still working fine. The car will do an occasional full charge discharge cycle to erase any developing memory effect which would show up as a low capacity pack.
The data from the test is at:
http://www.99mpg.com/workshops/mikessaturdayhybri/
 

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How about a Photovoltaic cell??

I have a 2 foot by 1 foot photovoltaic cell that is used for an RV to keep the battery charged. It plugs into the cigarette lighter. Any ideas if this would help charge the IMA batteries while parked in the sun during the workday? I drive 22 miles to-and-from work and usually arrive at work or home with only about 1/4 charge remaining in the batteries. If I could charge during the day it might help. Any thoughts?
 

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Re: How about a Photovoltaic cell??

MotoMark said:
I have a 2 foot by 1 foot photovoltaic cell that is used for an RV to keep the battery charged. It plugs into the cigarette lighter. Any ideas if this would help charge the IMA batteries while parked in the sun during the workday?
Hi and welcome. :)

Your Pv panel probably outputs about 15-17v and is totally unsuitable to charge the IMA battery directly, you need 10 panels in series to get the right voltage (170v) or so. It's not worth carrying the weight of the panels around to charge the IMA battery at present, so forget that. The Ima battery can be trickle or boost charged using other power sources, but it's a serious mod with lots of potential problems and dangers.

Your panel depending on it's wattage may be suitable to charge the 12v auxillary battery via the lighter plug, but the benefits are limited, and if the panel is too big you may overcharge your 12v battery unless the charge is controlled on a sunny day.

Have a go with the forum search option, there is quite a bit of info sprinkled about on these issues/topics, they have been discussed before.

Peter
 

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Thanks, sounds like charging through the 12 volt battery doesn't get to the IMA battery, or at least not enough amps or watts to make a significant recharge, particularly since the 500mw at 12 volts wouldn't make much of an impact on 144 volt IMA pack. Thanks for the input!
 

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This subject has been brought up many times in many forms.
Since the SOC when you start the charge is not measurable, and the only voltage based way to tell when you should stop charging is the raise then dip at the 100% SOC point.
http://www.99mpg.com/Data/resources/dow ... nation.jpg

The SOC will reach 100% SOC with any external charging system that is not able to measure and compute SOC based on current in and out of the pack.
This 100% charge each day would likely do some damage or life shortening unless the charge current was small. I believe Armin used 300MA as his max charge, when he was doing this with his used pack.
Armin, are you grid charging the new pack?
 
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