Car parking heater but... with BATTERIES? :phew:

[Erwin Ried]

I have a 2012 hyundai and as you can see winter is coming here in norway:


Soon I will need to start scraping ice and removing snow every morning... there is a solution> webasto parking heaters but they are 2000 USD or more, plus installation which can be easily another 2000 USD, so I was thinking what if I make a cabin heater with batteries.

Is this a crazy idea? 

Idea:



Battery and charger (2 of these to rotate in office and house): 48V 58Ah https://www.aliexpress.com/item/1005001316820830.html?spm=a2g0o.productlist.0.0.72bd7fe523NkKB&algo_pvid=cbb6ea52-ec49-4d71-af09-6513921ede3a&algo_expid=cbb6ea52-ec49-4d71-af09-6513921ede3a-4&btsid=0bb0622a16035439498188313ed59e&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

Heater: 48V  800W https://s.click.aliexpress.com/e/_99Vqy7

PTC heater element (220V or 110V but used at 48V just to keep the batteries warm): https://s.click.aliexpress.com/e/_AcupL5

So, remote control via 433. I guess I would need 30 mins per battery of runtime to keep the car over 20C while the environment outside is -10C. The PTC heater element will just be used on idle times.

Opinions? Could that work ok?   

[Gyro]

My solution is a 2kW portable fan heater and extension lead. Run it in through a back door and sit it in the middle of the back seat, facing forward. Leave the door on the secondary latch to avoid the cable deforming the rubber seals.

It's not the most technically exciting method, but in a hard frost in the UK, it will clear and dry all of the windows and give you a lovely warm interior in the time it takes to eat breakfast (usually leave it just on the 1kW setting). I've been using this method for years.

I think you're underestimating the amount of heat you need to produce from that 48V battery supply, probably by an order of magnitude.

[Stray Electron]

  If I read your drawing correctly, you plan to use a 20,000 mAH battery to operate an 800 Watt heater.   That works out to 800W/48V =  16+ amps power demand and using a 20 Amp Hour battery you'll only get slightly over one hour of heating.  And that's if the battery will even supply 20,000 mAH when operated at that current demand, mostly likely that rate will decrease the battery capacity considerably. Also drawing out more that about 50% of the battery's capacity will shorten the battery's life considerably.

    Unless you plan on filling the trunk with batteries, you need to use an external AC mains for power.

[Cerebus]

I think you're underestimating the amount of heat you need to produce from that 48V battery supply, probably by an order of magnitude.

You have a point, but it may not be as bad as you think. Your 1kW over breakfast represents, what, 15 min x 1kW = 900 kJ. The 48V 20Ah battery represents 2,880 kJ total stored energy or 900W at a 1C discharge rate. That battery could match your 1 kW heater for 15 min at 1.11 C discharge rate.

So far, rough parity. BUT, Norway is not Britain. It gets just a tad colder over there than over here. I think the first order of business would be to calculate the total heat load that needs to be applied, worst case, in Norway and work from there. One really needs a model of how much metal, glass and frost needs to be heated from what starting temperature to what finishing temperature.

[Erwin Ried]

My solution is a 2kW portable fan heater and extension lead. Run it in through a back door and sit it in the middle of the back seat, facing forward. Leave the door on the secondary latch to avoid the cable deforming the rubber seals.

I park outside, and the extension lead would be pretty substantial, 30-40 meters. I would love to permanently install a heater to avoid the seal deformation as you say... if I had a AC outlet near the car.

I think you're underestimating the amount of heat you need to produce from that 48V battery supply, probably by an order of magnitude.

    Unless you plan on filling the trunk with batteries, you need to use an external AC mains for power.

Ahaha, I think I want 2 backpacks, one while I am in the office, one while I am home and rotate them in that way. I am ok with 30 mins of heat at 800W, just to kickstart the melting and defogging.

What I do now is to remove the snow, and then wait 10 minutes inside with the car on idle so everything gets melted


If I knew before I would tried to find a car with parking heater and steering wheel heating built-in  (I had to send my car to the shop and they gave me a rental for couple of days... and the rental had that remote heater... with I had no idea of their existence before moving to norway

You have a point, but it may not be as bad as you think. Your 1kW over breakfast represents, what, 15 min x 1kW = 900 kJ. The 48V 20Ah battery represents 2,880 kJ total stored energy or 900W at a 1C discharge rate. That battery could match your 1 kW heater for 15 min at 1.11 C discharge rate.

I am happy with:

• full blast heat at 800W for 10 mins?
• intermitent heat for 20 mins?
• survival of the battery for 12-20 hrs with the ptc pad heater

[Rick Law]

Beware where you aim your heater.

This is over two decades ago, but should still apply unless material changed.

Deep in Chicago winter, I had a coworker who used a 1.5kw/1.6kw (100/110V)  heater (with fan), on extension cord to warm up and de-ice.  The heater was on the back seat.  However, while the center was aimed and hit the front wind shield, part of the heated air was blowing on the back of the front seats.  The vinyl didn't like it...  It deformed.  If I recalled, it was probably for over 1hr (time enough to eat dinner) but under 2hrs.

Car's interior heater is made for the car.  If I have to use an external heater, I'd go with much less powerful heater if there is a possibility that you leave it running long.

EDIT: adding this:
Just in case you wonder how he could plug in the power at the restaurant...   We were working there, college jobs back then.

[Gyro]

Good point Rick.

Extended operation would indeed raise the internal temperature excessively, especially when the Ice has melted. My fan heater does have a room thermostat function, but I can't claim to set it sensibly. 10-15 minutes [Edit: just before leaving home,] is about right for defrosted and comfortable, I wouldn't push it further than that!

[Erwin Ried]

Based on the answers, now I am thinking I should make 2 units that contain all the components, including the charger:



a) infrared thermometer pointing forward to avoid heating surfaces too much
b) ambient cheap humidity /temp sensor
c) battery temp sensor
d) 433 mhz receiver and ESP32

While the device is charging, the signal only activates the one which is not charging in that moment (so only 1 remote for both units). Maybe I should get the larger 58 Ah battery, and heat the cabin very slowly.

I am thinking the idea is not that crazy. Probably it wont be that bulky either. Just like a heavy lunchbox I place on the seat pointing forward/up

[Per Hansson]

The most common solution in the Nordics is an electric heater from Defa or Calix.
These are usually a heater block for the motor, or (IMO) less preferable a water heater for the cars coolant.
And inside the car a regular 230VAC outlet for a heater.
Just putting it out there if you did not consider it.
A 40m extension cables sounds allot more sane than a battery based heater IMO.

P.S: I would never ever trust a cheap lithium battery from China with this kind of load.
You are just begging to start a fire with that kind of abuse of a cheap China battery.
Also the battery linked in the OP claims to be 58Ah but is really 5.8Ah:
"The battery was tested in the lab and not really 59,000 mah is actually 5.9 ah and only lasts between 6-7 km and a disappointing ride!"

[Renate]

A friend of mine was doing a van conversion and wanted to use electricity (from solar) for general heating.
I tried to talk them out of it. People do not appreciate how much energy is required for heat.

I have an RV. It has gasoline fuel, propane for heating and cooking and batteries.
Besides the truck battery I have two "golf cart" (6 V) batteries that together weigh ~60 kg (~130 lbs).
I made a graphic to show the relative energy stored in gasoline, propane and batteries (based on 100% discharge!)

Needless to say, I'll stay warm with my propane furnace.

[Stray Electron]

I park outside, and the extension lead would be pretty substantial, 30-40 meters. I would love to permanently install a heater to avoid the seal deformation as you say... if I had a AC outlet near the car.

  I don't know if you own your own home and property or not but if It were me, I would run an underground cable out to my parking area and mount an AC outlet as close as practical to my parking spot. Not only could you then use a car interior heater but you could connect an engine block heater, coolant heater and a battery charger or anything else that you desire.

   OTOH the temperature here is still about 86F during the day so we have very little need for heating.

[Cerebus]

A 40m extension cables sounds allot more sane than a battery based heater IMO.

If you live most urban places, a 40m extension cable to roll out into the [public] street and back in again, in snow, sounds like a pain in the backside to me. Trip hazard, public liability, buried in snow, possibly exposed to cleated footwear - fill in the rest of the list of hazards yourself, I suspect it could get quite long. Sounds like a lot of trouble to me.

[Mazo]

I see you wrote that you remove the snow and then sit in the car while the engine is idling.Why so?
Most people in my country(far warmer than Norway,but still -20degC a few times per winter and alot of mountainous areas that are norway like),clear a small opening around the driver's door,enter the car,start the engine,turn the heater on max,and proceed to clear the rest of the car.This normally gives the required idle time for the engine to start giving off some heat.
Am I missing something?

[james_s]

Oh man, I feel cold just looking at that photo, brr!

When I was still commuting by car I also would occasionally use the portable heater on an extension cord plugged into a timer thing. I ran it in the driver's door so I wouldn't forget and drive off with the cord connected. Made a real difference on the handful of really cold days we get in the winter, but I park in the driveway in front of my house so the cord is not a problem.

If you want to use batteries you'll need quite a powerful pack to hold enough energy to warm up a car in that climate. You'll also need to think about recharging those batteries, will you carry the pack into the office when you get to work and charge it there? Otherwise I suppose you could have two packs and charge one in your home each night while the other sits in the car ready to power the heater in the morning.

[mzzj]

Soon I will need to start scraping ice and removing snow every morning... there is a solution> webasto parking heaters but they are 2000 USD or more, plus installation which can be easily another 2000 USD, so I was thinking what if I make a cabin heater with batteries.

Car shops like to ream you on both webasto prices and installation. (Norway is expensive but for example in here you should be able to get it installed for about 2000 euros total.)

Webasto kit is something like 800 euros from Germany https://www.ebay.de/itm/Webasto-Standheizung-Benzin-Thermo-Top-Evo-4-Uni-EBK-MultiControl-Car/292553710120?epid=21030509421&hash=item441d8f5a28:g:aMUAAOSwWTZcasF-

Or if you are enough adventurous to install unknown li-ion batteries from Aliexpress you might as well go to chinese webasto/eberspächer copy (bit over 100 euros) https://www.ebay.de/itm/12V-5KW-Diesel-Standheizung-Luftheizung-LCD-Schalldampfer-LKW-PKW-Wohnmobil-NEU/163430807539

And that aliexpress battery is a scam as pointed out earlier.   

[Jeroen3]

At work someone put a remote starter unit in his car. Which also works for a frozen window, but probably not to clear a meter of snow.

Having a interior preheater installed by professionals can be done for €2k. I do not believe it costs $4k, you shouldn't be asking these things with your brand dealership.

[Renate]

I've never heard of Webasto, but now we're talking heat! 4-5 kW
My propane furnace is 20,000 BTU/hr, better than 5 kW

[Erwin Ried]

Soon I will need to start scraping ice and removing snow every morning... there is a solution> webasto parking heaters but they are 2000 USD or more, plus installation which can be easily another 2000 USD, so I was thinking what if I make a cabin heater with batteries.

Car shops like to ream you on both webasto prices and installation. (Norway is expensive but for example in here you should be able to get it installed for about 2000 euros total.)

Webasto kit is something like 800 euros from Germany https://www.ebay.de/itm/Webasto-Standheizung-Benzin-Thermo-Top-Evo-4-Uni-EBK-MultiControl-Car/292553710120?epid=21030509421&hash=item441d8f5a28:g:aMUAAOSwWTZcasF-

Or if you are enough adventurous to install unknown li-ion batteries from Aliexpress you might as well go to chinese webasto/eberspächer copy (bit over 100 euros) https://www.ebay.de/itm/12V-5KW-Diesel-Standheizung-Luftheizung-LCD-Schalldampfer-LKW-PKW-Wohnmobil-NEU/163430807539

And that aliexpress battery is a scam as pointed out earlier.

Well, the second one is just for diesel. I would install the webasto myself but in one moment I though having a small battery pack would not be a bad idea, a small portable heater instead of few hours cutting into my fuel supply and vents.

I see you wrote that you remove the snow and then sit in the car while the engine is idling.Why so?
Most people in my country(far warmer than Norway,but still -20degC a few times per winter and alot of mountainous areas that are norway like),clear a small opening around the driver's door,enter the car,start the engine,turn the heater on max,and proceed to clear the rest of the car.This normally gives the required idle time for the engine to start giving off some heat.
Am I missing something?

Snow is good insulator, if snows a lot while you are in the office, the heat of the car will only heat the first layer of the snow and it will take forever to melt everything, I just remove most of the snow and then wait.

[Erwin Ried]

:
"The battery was tested in the lab and not really 59,000 mah is actually 5.9 ah and only lasts between 6-7 km and a disappointing ride!"

Ohhh good catch. That will give less than 10 mins of runtime. I might consider then a 400W heater, since the parts are so cheap it wont be a waste just to assemble a test rig before deciding on webasto or not

[Erwin Ried]

If you want to use batteries you'll need quite a powerful pack to hold enough energy to warm up a car in that climate. You'll also need to think about recharging those batteries, will you carry the pack into the office when you get to work and charge it there? Otherwise I suppose you could have two packs and charge one in your home each night while the other sits in the car ready to power the heater in the morning.

My idea is to have 2, with a carrying handle and AC coord attached in a small spool. So I enter the office with one and plug it in, and then back home and plug that other one. There is a button on the pack to trigger the "other" brother to start heating up, so everything is selfcontained.

[mzzj]

Based on my shady memory 1kW Calix or Defa needs 1h even on moderate temperatures like -10c and over 2 hours on -20 to make any difference.  My current car has gasoline webasto that heats the car every morning at 07:00 

You are looking at two 2kWh battery backs at minimum if you want this to really work as intended.

[mzzj]

1400 euros for one 2kwh battery pack if you go for brand name cells and you get maybe 700 cycles out of it if you are lucky.
2 euros per heating ignoring the electricity cost. 

In comparison 4kW webasto uses 0.5 L/h (diesel) fuel at full blast.
30 minutes gives you same 2kWh as above. IIRC gasoline was bit over 1.5 euros/l in Norway = 0.38 euros per heating

Liquified dinosaurs are still damn cheap compared to electricity if you have to use batteries as a storage!

[Erwin Ried]

I got an answer for the only workshop that brings webasto to my town, it is 35000 kr = 4000 USD



Car was 120000 kr 1-2 years ago, so it makes no sense really 

Liquified dinosaurs are still damn cheap compared to electricity if you have to use batteries as a storage!

True... I might need to decide on a chinese webasto clone then...

[mzzj]

I got an answer for the only workshop that brings webasto to my town, it is 35000 kr = 4000 USD

Damn! But not really surprising, Norway tends to be expensive both on parts and services and up there(Tromso?) you don't have too many options to choose. And in current situation going "shopping" to Sweden or Finland is also pretty much out of question.

[Renate]

I'm sure that a lot of that cost is installation.
To neatly and properly retrofit something in a vehicle takes a lot of time and care.
It's something that you could do yourself, maybe not as neatly if you didn't invest the time.