blackheart
Posts: 131
Joined: Sun Mar 13, 2016 9:41 am
Location: Portland Or

Re: Upgrading Heating System - Independent Battery Source

Thu Feb 16, 2017 2:32 pm

Ok - side stepped the pusher trailer for a while - expensive helper project...
BUT, I did order a cradle for my Dolphin 48v 11aH ebike battery from Luna Cycle.... Why? So I can mount the 10 lb battery in the car safely and wire it to a 48V heating element that I will mount someplace in the heating fluid system. I am thinking close to the inlet side of the heater core, so there will be less heat loss for water (coolant) traveling around in our 'engine' bay (what do you call the space under the front hood in our little cars???)
This should give me about 500 watts of heater helper power. If that is too small, Luna is also selling a 48v 17.5aH battery they call the "Killer whale". That would give you around 700-750 watts of power. Not enough to drive all day, but should be enough to warm me and passengers in my normal 30 min drive time. And the 'heater' battery can be charged at my work, or at a friends house, or pretty much anywhere - and NO diesel....
Thoughts???
'Is treading water actually swimming - or just prolonged drowning"

-2012 MItsubishi I-Miev - BlackJack
-1989 GMC Sierra 4x4
-2015 RadRover Emonster bike


EVSEupgrade

Don
Site Moderator
Posts: 2544
Joined: Thu May 10, 2012 3:55 pm
Location: Biloxi MS

Re: Upgrading Heating System - Independent Battery Source

Thu Feb 16, 2017 4:04 pm

blackheart wrote:Thoughts???
500 watts isn't much heat . . . . 750 is not much times 1.5 :lol:

Before you go to the trouble, I would pick a cold morning and put a small 120 volt household heater set on 'Low' (should be 500 to 750 watts on most of them) in the car for 20 minutes or so and see what that gives you

I know that using the remote heating system with the OEM L1 EVSE (8 amps . . . . probably provides about 750 watts of heat) does very little to heat up the car in 20 or 30 minutes before it shuts off, so maybe you'll discover that 500 watts isn't worth the trouble??

FWIW, there are 3,412 btu's of heat in a kilowatt hour of electricity and 8,687 btu's in a cupful of diesel fuel . . . . and the car comes with a 5 kw heater

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1994 Miata 60K miles - Soon to be sold
1979 Honda CBX six into six

blackheart
Posts: 131
Joined: Sun Mar 13, 2016 9:41 am
Location: Portland Or

Re: Upgrading Heating System - Independent Battery Source

Thu Feb 16, 2017 6:34 pm

On cold mornings, I have pre-heated the car with my L2 plug. When leaving the house, I see the Heater using electricity (via Canion) within one mile. By the time I get to work, it shows that I have used about 500 watts. So, for my ride to work, all I should need is 500-700 watts to keep things up to temp. True it is not very much. But it sure seems to kill my range. If I get 4 miles per KW, that is 250 W per mile? So, the heater 'seems' to only take about 4 miles of range - but my RR meter seems to take a bigger hit than that.
But, If all I needed was another 4 miles (2 miles savings to work and two miles savings leaving work) it may just be worth it.
Just looking for something to get me over the edge on the cold days. During the times of year that I don't need the heat - I have range to spare. But during the winter - the miev becomes a two point car - work and back. I take the truck to go get the wife... All I need is a couple more miles ;-)
Plus, I have the battery, the cradle was $30. An element is $30ish. I work at a manufacturing company, so I can make a reservoir from scrap. A thermostat and some wire - it might be a fun project.
Though I would probably get more 'savings' from insulating the car and existing heat system better.
No offense - I am not to the point of needing that much heat - and if I can do it without diesel = win.
'Is treading water actually swimming - or just prolonged drowning"

-2012 MItsubishi I-Miev - BlackJack
-1989 GMC Sierra 4x4
-2015 RadRover Emonster bike


EVSEupgrade

Don
Site Moderator
Posts: 2544
Joined: Thu May 10, 2012 3:55 pm
Location: Biloxi MS

Re: Upgrading Heating System - Independent Battery Source

Thu Feb 16, 2017 8:47 pm

By all means, give it a shot! - I wasn't trying to talk you out of it . . . . just suggesting you try something simpler to see if 500 watts of heat would make much difference

More neat things have been learned about these cars by those with a bit of ingenuity who were willing to give something a try to see what's practical. If you're only looking to 'save' a few miles of range, this just might be something that will work for you. If the car is already preheated when you leave, maybe some sort of portable heater sitting on the floor would do the job without needing tomodify the car to build something in permanently?

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1994 Miata 60K miles - Soon to be sold
1979 Honda CBX six into six

blackheart
Posts: 131
Joined: Sun Mar 13, 2016 9:41 am
Location: Portland Or

Re: Upgrading Heating System - Independent Battery Source

Fri Feb 17, 2017 9:06 am

Didn't take it that way at all - And me being a newb to all things electrical - this forum has been a great place to learn - so that's why I made the post - 'give your thoughts' ... I know it won't make much - but looking at my Canion during my morning commute, when I am using heat, 500-700W seems to be the ticket. And I have the battery - so why not? :D

However, I am very interested in hearing what folks have done as far as insulation. I can tell the second the heater is turned off in the little car. Due to living it the wet NW, I haven't crawled around much under the car this winter, but I suspect that there could be some fairly draft inlets along the firewall, or something. Maybe the cabin is just not insulated at all? I have seen people post about wrapping insulation around the hoses of the heating system - I hope to do some of that during our 'dry season' (best two weeks of the year!!).

Per the interwebs "One BTU is the amount of heat energy required to raise one pound of water by 1ºF. Water weighs 8.33 pounds per gallon so we can calculate that one gallon of water requires 8.33 BTU to raise the temperature 1ºF." But I read (and correct me if I am wrong) that our little car's heating systems only hold like 2.2 quarts of fluid. And since the fluid is being actively cooled by the air flow over the heater core, I am not sure what those losses are.
The ebike battery (not accounting for losses) should equate to 1700ish BTU's right? So, i should be able to raise the temp of 1° (1700/8.33) 204 times??

Like I said, new to electrical math - but it should heat it some. Between that and some insulation (to make the heating system more efficient) It should help some - don't you think????

oh well, if it doesn't, I'l have a cradle to use the batter elsewhere ;-)
'Is treading water actually swimming - or just prolonged drowning"

-2012 MItsubishi I-Miev - BlackJack
-1989 GMC Sierra 4x4
-2015 RadRover Emonster bike


EVSEupgrade

Don
Site Moderator
Posts: 2544
Joined: Thu May 10, 2012 3:55 pm
Location: Biloxi MS

Re: Upgrading Heating System - Independent Battery Source

Fri Feb 17, 2017 9:25 am

Have you read through this thread?

viewtopic.php?f=9&t=224&hilit=heater+insulation

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1994 Miata 60K miles - Soon to be sold
1979 Honda CBX six into six

blackheart
Posts: 131
Joined: Sun Mar 13, 2016 9:41 am
Location: Portland Or

Re: Upgrading Heating System - Independent Battery Source

Fri Feb 17, 2017 10:19 am

I have a bit - but I will run through it again
Thanks!!
'Is treading water actually swimming - or just prolonged drowning"

-2012 MItsubishi I-Miev - BlackJack
-1989 GMC Sierra 4x4
-2015 RadRover Emonster bike


EVSEupgrade

Aerowhatt
Posts: 351
Joined: Wed Jan 28, 2015 1:52 pm

Re: Upgrading Heating System - Independent Battery Source

Fri Jan 19, 2018 11:54 am

Bump! So Getting back to this project. I have had all of the parts etc. and a completed design for months. But once we got the recall notice on the airbags I put off going forward. Unlike some of my other mods to the car which are, for all practical purposes, invisible. This one will be obvious, right under the hood. Like everything I do, with something under warranty, the design allows reasonably easy removal with no trace that it was ever added. However in the interest of laziness I wanted to get the airbag done first. Got my wife’s cars airbag done last week and (another story :x ) I am NOT looking forward to going back to the dealer for my own to be done.

We had a rare day for NM recently so I took the opportunity to do some testing. Conditions were dark overcast and 29 Deg F. I preheated the car at 240 volts input. Then went for a long drive. Dark overcast is important since the sun here at 5000 ft elevation is so powerful. If the sun is out, far less heat is required. Mainly my goal was to measure the best practice usage and resulting power consumption of keeping comfortable. I didn’t dress any warmer than I would for, say a grocery run in an ICE. I don’t like to drive with a coat on (so no coat) no insulted boots, no hat, gloves or anything like that. Just good over the calf socks, summer hiking shoes, jeans and a t shirt under a long sleeve henley.

Doing hiking trips to the mountains for two full winters (this is the third) has helped me find the best most efficient way to use the stock heat. It makes sense when you think about it and is different than we are conditioned to use the heat from years of ICE driving.

Preheat the car if you can.
Use the seat heater. I usually turn it off after ~10 minutes because it gets too hot
Direct the heat to the floor only, on recirculate (it will keep all of you warm, heat rises).
One notch toward defrost if needed to prevent fogging.
Start driving with the fan on high (I like the setting just below high because it is a bit quieter)
Temperature setting should be where ever you need it to be. I generally start high and end up on the second or third position up from the green dot.
If and when the heat is adequate inside the car turn the temperature down, not the fan!

#6 is critical! The heated fluid goes from the heating element right into the cabin. The more heat that you take out of that fluid before it makes the long trip outside of the cabin (under the hood etc.) the less heat is wasted to the cold environment.

So back to my test run. I drove around town town for 1.5 hrs using the Canion heater power graph to average my power consumption for heating. The average for the trip was 638 watts/hr. That (generously) equates to about 3 to 4 miles of worth of lost driving power (per hour) for staying comfortable. I know from previous non preheat trips at around 33F that approximately an extra 800 watts of power is required to warm the car up inside (just the front, heat directed to floor only using the “max” button until the the chill retreats). Which yields ~1500 watts for the first hour starting out cold (up to ten miles worth of range).

The 2014’s have a styrofoam piece under the front carpeting. I don’t think the 2012’s have this and it would make a difference, I’m sure. But overall, if one optimizes usage of the heating built into the car and it isn’t to to cold (29F is reasonably cold though).

The point of my test run was to take advantage of the unusual weather conditions to see if the 1200 watt output of the designed separate battery powered heating unit would be enough. Looks like it should be even capable in worse conditions than I encounter. Perhaps with an initial boost from the onboard system to speed the initial response time of warming the cabin when not preheating from the mains.

Aerowhatt
2014 cool silver ES, acquired new 4/2015
2014 Labrador Black Pearl ES, acquired new 3/2016

JoeS
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Location: Los Altos Hills, California

Re: Upgrading Heating System - Independent Battery Source

Fri Jan 19, 2018 11:08 pm

Aerowhatt wrote:...Got my wife’s cars airbag done last week and (another story :x ) I am NOT looking forward to going back to the dealer for my own to be done...
I just had all the recalls done on my two i-MiEVs over the last couple of days (including vacuum pump replacement) and I hope the squishy brake pedal is just temporary...
Aerowhatt wrote:If and when the heat is adequate inside the car turn the temperature down, not the fan! #6 is critical! The heated fluid goes from the heating element right into the cabin. The more heat that you take out of that fluid before it makes the long trip outside of the cabin (under the hood etc.) the less heat is wasted to the cold environment.
I understand the logic and am now doing that, although it's disconcerting to see the RR gauge react to the fan and not the temperature control!
Aerowhatt wrote:So back to my test run...
Great that you've got data for the "before" scenario. Looking forward to your installation which is environmentally 'cleaner' than the diesel heaters our northern brethren have been using. Where will you physically locate your 36v LiFePO4 battery pack? Do you think there's enough time to recharge that 36v pack using a dc-dc off 12v in your usual main pack recharging regimen timeframe? I'm impressed that you're doing this as a fully automatic hands-off installation (mine would be something Rube Goldberg would be proud of) :geek: .
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

Aerowhatt
Posts: 351
Joined: Wed Jan 28, 2015 1:52 pm

Re: Upgrading Heating System - Independent Battery Source

Sun Jan 21, 2018 12:13 pm

JoeS wrote:
I just had all the recalls done on my two i-MiEVs over the last couple of days (including vacuum pump replacement) and I hope the squishy brake pedal is just temporary...

Yeah dealers, sheesh, seems like they screw up more than they fix! They were pushing me hard to change the transmission fluid in my wife's car. Service requirements say 24 months, or 30k miles. Hers is at 21 months and 11K miles. They made sure to put it on the paperwork that I refused the service! $118.00 plus tax they want for that. Amazon has the exact Mitsu tranny fluid for $12.88 per quart (car takes .76 quart for a refill). I'll definitely do it myself to prevent mechanical problems down the road. Now what kind of documentation do I need to not have warranty issues?? Two witnesses and my lawyer present? That would cost the same but at least I would know it was done right ;) . I need to figure it out and do mine before I take it in for the airbag recall. I'm at 32 months and 22k miles. So past due in their eyes :lol:

JoeS wrote:
Great that you've got data for the "before" scenario. Looking forward to your installation which is environmentally 'cleaner' than the diesel heaters our northern brethren have been using. Where will you physically locate your 36v LiFePO4 battery pack? Do you think there's enough time to recharge that 36v pack using a dc-dc off 12v in your usual main pack recharging regimen timeframe? I'm impressed that you're doing this as a fully automatic hands-off installation (mine would be something Rube Goldberg would be proud of) :geek: .

I have decided to get AC power from the mains instead of taxing the DC to DC. It's a 40 amp hour 36volt pack, so three hours at 15 amps. Easy enough to source a charger that runs on 240AC and puts out 15 to 20 amps "36 volts". Ideally picking up the AC power between the charging port and the cars charging unit. That way it will charge while the car charges and be disconnected by the EVSE when the car finishes charging. Honestly though I'm feeling gun shy about proceeding with the installation. With our Canadian friend having to fight for having his traction battery warranty honored because of the diesel heater installation. :roll: This is what I was worried would crop up when Nissan got a controlling share of Mitsu motors. Still on the fence about battery placement. Either the cars trunk or the hitch mounted tool box. Tool box makes more sense for safety but I don't always have the rack and tool box along for the ride :?

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Aerowhatt
2014 cool silver ES, acquired new 4/2015
2014 Labrador Black Pearl ES, acquired new 3/2016

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