Honda Insight Forum banner
81 - 100 of 135 Posts

·
Linsight Designer
Joined
·
4,479 Posts
If we power from the 12 volt rail, then we can't use the heater when the car is off, even if the grid charger is plugged in... we'd need to add an additional 12 volt grid charger, and it would need to be able to supply 20 amps, so it wouldn't be cheap.

I have no issue populating the several hundred resistors on the existing PCB design... pick and place machine sits unused 99.9% of the time, so might as well put it to use. The discrete resistor concept should work for 5AhG3.

When it comes to things like conductive tape, fabric, etc, those types of assemblies are incredibly difficult to do safely. If you're powering them from 12V, then much less of an issue, but again you need a bunch of current at that low voltage.
 

·
Registered
Joined
·
404 Posts
I'm not sure if it would be helpful but they have long flat vapor chambers available in lengths up to 55cm. They are 3 mm thick so I don't think they'll fit between the ribs.


There are also a number of graphite and graphene based heat spreading films/sheets.
 

·
Premium Member
Joined
·
2,988 Posts
I haven't seen the commercialized vacuum panels you mentioned before. Neat! As you mentioned, they look pretty fragile... not sure they would hold up in the hands of most G1 Insight owners ;). Since you've used them, how much abrasion resistance do they have? If a bolt head rubbed on them for 20000 miles, do you think they'd still be vacuum sealed?
The panels are not designed for structural loads .. but are fine in many distributed compressive loads , Panasonic rates them for a max of 9.8 lbs per square inch (15mm thick version) .. the roughly ~200 square inch bottom of a IMA battery sized box would allow up to a max of 1,980 lbs .. if evenly distributed across that entire ~200 square inch surface area .. bumps/shocks/etc will mean that maximum would have to be de-rated some .. for example allowing for 10Gs of shock/bump force would still allow for up to a max of 198Lbs in that ~200 square inch.

But .. the panels OEM exterior film layer would not withstand much of anything .. no point pressure , no abrasion , etc .. The exterior film layer kind of has to be treated like the exterior of the pouch cell style batteries .. any load distribution , abrasion resistance , etc .. all has to come from some non-OEM layer one builds into the overall package design .. you either need to have deep enough pockets and a large enough project run to have Panasonic make them the specific size you want , or you have to design your product to fit the common used 13 different sizes that DigiKey distributes.

These vacuum panels are likely overkill unless the entire battery is wrapped. Even a couple small holes for airflow (when desired) would compromise the overall insulation value of the pack. Honestly I think 'standard' non-flammable insulation (e.g. rockwool) is probably sufficient (in conjunction with a heating element). No need for exotic materials... even an R-1 insulation rating would be a vast improvement versus the exposed aluminum surfaces inside the IMA bay.
yup

Aside: I believe aerogels have a higher R-value (and are also more fault tolerant), but they are also even more expensive than the vacuum panels you mentioned.
All the Aerogel that I've seen .. are all worse than Panasonic's VIPs .. in terms of raw thermal insulation.

Panasonic rates their VIPs as 0.002 W/mK thermal conductivity

AFAIK .. Silica based Aerogel (as a solid chunk of foamed glass) .. is from :
~0.03 W/mK .. ie about 15x more heat loss than Panasonic's VIPs.
to at best ~0.004 W/mK .. ie still at least 2x more thermal heat flow than Panasonic's VIPs.

Of course Aerogel has two rather large pros:
#1> You can fairly easily mix the small bits of Aerogel with other things to make a blanket or such you mix the thermal properties .. soo the blanket won't be as good as a solid chunk .. but mixing like that is not an option with VIPs.

#2> Aerogel can be cut , drilled, etc and the pieces you have left still keep their thermal insulation properties .. VIPs can not be cut , drilled, etc without their R value dropping down to similar to regular foam / fiberglass insulation about ~R5 per inch of thickness.
 
  • Like
Reactions: mudder

·
Registered
y2k silver'sight, hch1 5spd, snow tires
Joined
·
160 Posts
Discussion Starter · #84 ·
okay don't laugh me out of the room.
is the 'big breaker' the only way to isolate the hv pack from the ima?
could that breaker be substituted with a solid state relay, controlled by libcm to disconnect ima during idling, 'if low temperature qualifier is met'? than the ima can't hurt the battery if it's too cold, and the ima could be free'd up to drive a hv pcb heater. ??
i'm trying to envision a self sustaining system.
don't get me wrong mudder's grid heater is awesome. it solves the 'overnight' cold, and the 'im gunna leave for florida for two weeks cold'
there'd have to be a way to burn gas to heat the battery for me, even if i have to put a fish house heater by the spare tire.
problem is if i drive to a job im not going to use a client's electric meter to my benefit. i dont like the idea of hunting for outlets in the snow.
I don't know
if im dumb please explain why
 

·
Registered
Joined
·
404 Posts
Your not going to have any problems heating the battery using cabin heat once the code is changed to turn on the fan.

Another option is to put a computer fan in the Intake port for the IMA fan. Only a small amount of airflow is required to for the LiBCM intake sensor to be able to detect an increase in cabin air temperature.
 

·
Registered
Joined
·
263 Posts
I piped A/C directly in to the IMA case during the summer here in AZ. I often wondered if it was only providing superficial cooling during my 25 minute commute. Once the batteries are hot or cold all the way to their core, I wonder the amount of benefit provided by cabin air.
 

·
Premium Member
Joined
·
2,988 Posts
i'm trying to envision a self sustaining system.
It ultimately comes down to rate of heat loss .. the only way to be 'self sustaining' .. would be 1st to reduce the rate of heat loss .. ie insulate .. then add some form of passive energy collection (like solar PV on the car) to make up for the difference lost over time.

there'd have to be a way to burn gas to heat the battery for me
Yes you can do that .. until the car runs out of gas.

Option#1> ICE modded
A remote starter and a remote FAS both being controlled by a thermostat .. and heat ducted to the battery.

Option#2> gasoline directly fueled heater.
Some van life people use them .. it's a heater that runs directly off of gasoline .. wire it up to be controlled by thermostat and plum it's heat into the battery.
 
  • Like
Reactions: trickle

·
Registered
y2k silver'sight, hch1 5spd, snow tires
Joined
·
160 Posts
Discussion Starter · #89 ·
It ultimately comes down to rate of heat loss .. the only way to be 'self sustaining' .. would be 1st to reduce the rate of heat loss .. ie insulate .. then add some form of passive energy collection (like solar PV on the car) to make up for the difference lost over time.
i want to insulate the outside of the ima and underside of the car. i don't like fiberglass or rock wool due to the health hazzards associated, i like foam board and sprayfoam but unsure of static electricity with fans near high voltage stuff. im going to start looking into pv. i know it's an evolving technology im just not too up to date with it. recommend any resources? i painted an oak desk top last january outside below freezing ambient just by pointing the table surface towards the sun and it worked to my amazement. the sun heated the raw wood to over 70F and once it had the black enamel on it, it reached 90F on the surface with no wind. ive always wanted to try making a solar furnace with pop cans, maybe a fun project to dabble with soon. i typically park with the radiator facing the sun but this car doesn't offer much benefit from that with the front end design. this morning i opted to wrap my grill with pipe insulation instead and the heater sure works better now.
 

·
Linsight Designer
Joined
·
4,479 Posts
okay don't laugh me out of the room.
Only if you tell a bad joke.

is the 'big breaker' the only way to isolate the hv pack from the ima?
could that breaker be substituted with a solid state relay, controlled by libcm to disconnect ima during idling, 'if low temperature qualifier is met'? than the ima can't hurt the battery if it's too cold, and the ima could be free'd up to drive a hv pcb heater. ??
As long as the OEM MCM is present, disconnecting the battery from the HVDC bus would set of half a dozen P-codes. We also don't want to do this, as that would cause the DCDC to turn off when the engine is idling (HVDC bus voltage too low).

There are easier ways to disable regen/assist. Probably the easiest is to set the Regen/Assist Disable flags in the serial data stream LiBCM sends to the MCM over the BATTSCI bus. However, if we did this, then the MCM would still disable the DCDC converter at idle (HVDC bus voltage too low).

i'm trying to envision a self sustaining system.
don't get me wrong mudder's grid heater is awesome. it solves the 'overnight' cold, and the 'im gunna leave for florida for two weeks cold'
there'd have to be a way to burn gas to heat the battery for me, even if i have to put a fish house heater by the spare tire.
The battery heater PCBs will also work when the car is on (e.g. when you're driving). But yes, at idle the IMA system is always going to discharge because the IMA motor's bus voltage is too low.

problem is if i drive to a job im not going to use a client's electric meter to my benefit. i dont like the idea of hunting for outlets in the snow.
I don't know
if im dumb please explain why
See above: the board heater will also run while driving if the batteries are cold.
 

·
Linsight Designer
Joined
·
4,479 Posts
I piped A/C directly in to the IMA case during the summer here in AZ. I often wondered if it was only providing superficial cooling during my 25 minute commute. Once the batteries are hot or cold all the way to their core, I wonder the amount of benefit provided by cabin air.
It's pretty substantial.
@IamIan is correct that adding insulation to the IMA bay is the most efficient method to retain heat in the modules. My major desire to use rockwool is that it's not flammable.
 

·
Linsight Designer
Joined
·
4,479 Posts
12S 5AhG3 heater PCB:

...

I also played around with forced air heating, and ultimately decided it's not a viable solution when the car is off... you'd need to generate a lot of heat to overcome all the heat that gets lost when you're constantly heating cold cabin air... a 75 watt heater isn't going to cut it as long as air is blowing through the IMA bay:
 

·
Linsight Designer
Joined
·
4,479 Posts
The 18S PCB just shipped... that was fast!
The 12S PCB is ordered and should arrive right after Thanksgiving.

I also ordered enough components to build heater PCBs for QTY100 cars. It's super odd buying all the parts before testing anything, but that's how the process is nowadays. Wasn't sure which resistor value to use, but it'll be somewhere between 2000 and 2700 Ohms... I bought 2k0, 2k2, 2k4, & 2k7 reels.
 

·
Administrator
Joined
·
14,166 Posts
I've ££££ considered VIP's for insulating the roof of my lounge. It's the only room in my house I heat!

VIP's are very vulnerable to puncture and as we know Insights have lots of sharp metal and not that many flat surfaces.
However that said it might be possible to line the IPU with them if you get lucky with the sizes available..
Sides/front back might be OK. Top maybe on outside... Bottom underneath pack/mdm etc etc would be the really tricky bit.
 

·
Premium Member
Joined
·
1,442 Posts
Thanks Mudder! I appreciate you also designing for the pseudo 12S. In your video you said that there were only a few of those. Wouldn't you know it, I'm one of them. ;-)

-Bryan
 

·
Registered
y2k silver'sight, hch1 5spd, snow tires
Joined
·
160 Posts
Discussion Starter · #97 ·
Hand Tartan Aluminium foil Finger Gas


i don't know if this is a viable option for fomoco. i call this stuff forever tape because it will stick to hot/cold surfaces forever. i think it's commonly refered to as hvac tape for ducts. it is building code in my area now, all new forced air installs have all air leaks 'seams' sealed for efficiency. problem with this tape is it doesn't come off. ie if you have to pull a section of duct apart its faster to score it at the seam with a utility knife and retape it back together later. pitfalls of forced air is heating a lot of air in a house. a perk to forced air is that the furnace can be installed in an attic or basement or dedicated closet and the ducts can move the warm air to where you want it. since your using electricity you can greatly increase the efficiency because you don't need fresh oxgenated air for fuel. it can be a pure closed loop system with the ima being the lounge area, you have no idea how many times as a kid i got yelled at for not shutting a door all the way.
taping the ima cover isn't desireable for access. maybe a foam rubber tape could be used between the mating surface on the perimiter.
Rectangle Wood Floor Table Line

we used lots of thermopan also for making ducts, it doubles as insulation. it's cheap, like <.80 cents/ft2

i don't know if im helping. maybe tonight i will pull tools out of car and gut it so i can stare at it.
 

·
Registered
y2k silver'sight, hch1 5spd, snow tires
Joined
·
160 Posts
Discussion Starter · #99 ·
my extended forecast show's daily high's above freezing until nov 30. still have like 6'' of snow on the ground so its probably going to be a muddy mess where i have to work :( snow tires make decent mud tire's :)
 

·
Premium Member
Joined
·
2,988 Posts
@IamIan have you used those Panasonic VIPs to insulate the Honda insight cabin? It seems like it might be a good option above the headliner.
I have not yet used VIPs in my Insight .. I have been planning to use them on my next IMA battery upgrade I've been slowly tinkering with .. but I'm a turtle and have too many projects .. soo it takes me a while to get stuff completed.

I've tinkered / experimented some with them directly .. and have used them a few times in a few projects.

The trouble with trying to use them to insulate the Insight cabin is the geometry of the space vs the geometry of the panels ... flat square VIPs are best fit to square box style containers.

I am using them in the ~300kwh thermal storage I am building in my basement .. not yet 100% complete .. I liked being able to get about a R60 thermal insulation enclosure for that project .. and I didn't like the idea of eating space for 20 inches of height , 20 inches of width, 20 inches of depth , just in conventional insulation .. The VIPs can do that in about 2 inches .. Even after adding an outer and inner layer to protect the VIPs , It's still only 4inches instead of 20inches .. leaves the other 16 inches of space in the room , or internal volume space in the thermal storage unit.

I helped someone build a cooler with them .. they didn't want to pay Yeti $800 for one
They built a inside box and an outside box that protect the VIPs and formed a air tight sealed cooler .. a pace between the two to fit the VIPs .. and wala .. a thermally equally insulating cooler for about $300 instead of $800.

I helped someone build a insulated box for a off grid cabin .. they wanted to spend as little energy as possible keeping contents cold in summer , or warm in winter .. the small cabin had limited available space .. probably over kill , but they asked for my help to do it , and that's what we did.
 
  • Like
Reactions: trickle
81 - 100 of 135 Posts
Top