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> Though electric cars don’t need cooling grilles – batteries don’t get as hot and they’re chilled in a different way – many have them anyway to avoid looking w

> Though electric cars don’t need cooling grilles – batteries don’t get as hot and they’re chilled in a different way – many have them anyway to avoid looking weird. This actually isn't true. Electric engines do indeed release a lot less waste heat than internal combustion engines, but they also can't tolerate nearly as high of temperatures. And since heat dissipation is proportional to temperature, their cooling requirements (ie radiator) tend to be similar. Perhaps a bit less, but comparable. Teslas actually do have radiators; they're just mounted low, so they're less obvious. The same could be done in most other cars, although admittedly the electric engine might allow for easier flexibility of layout to accomplish this.

grogenaut 9y ago
but why does it need the grille, if the radiators are low then the grill is in the wrong spot, no?
- pySSK 9y ago
  Yep. Look at Model 3 design. Low radiator grille: https://www.instagram.com/p/BamdM3clVU3/ https://www.instagram.com/p/BamdM3clVU3/
  - tempestn 9y ago
    It's almost like the reverse of what the article is talking about. People expect electric cars to not need radiators, so they design the Teslas specifically to look different, even though in this way they're actually pretty similar to other cars!
taneq 9y ago
> Electric engines do indeed release a lot less waste heat than internal combustion engines, but they also can't tolerate nearly as high of temperatures. Eh? I thought both topped out around ~100 degrees C? Not that water cooling isn't a good idea for automotive electric drive motors.
- tempestn 9y ago
  Sorry, I guess I worded that poorly. In the electric case, it's specifically the batteries that need to be kept cooler. So while the whole system puts off less heat, at least the battery portion also withstands less, so still needs a significant radiator.
- deleted 9y ago
  [deleted]
- giobox 9y ago
  Rechargeable batteries of most designs are pretty heat sensitive. Too hot or too cold and the maximum range of the electric vehicle suffers. The drop off can be as high as 30% or so too, especially if you live somewhere with regular seasonal extreme temperatures. This is why as well as cooling systems, some EVs even heat the battery in the cold. The same thing affects Lithium Ion batteries in phones, cameras, laptops etc too.
  - phyzome 9y ago
    Hah, sounds kind of like LED lights -- way less waste heat, way more sensitive to what heat there is.
  - derefr 9y ago
    > This is why as well as cooling systems, some EVs even heat the battery in the cold. IC cars have that feature too, if you live somewhere like Saskatchewan. You need to plug the heater in at night (https://info.kaltire.com/wp-content/uploads/2015/03/Jan-6-PlugIn.jpg https://info.kaltire.com/wp-content/uploads/2015/03/Jan-6-Pl...) or the battery will be too cold to start the car in the morning.
    - YSFEJ4SWJUVU6 9y ago
      Block heaters are used in somewhat milder climates as well – even though a modern ICE will start quite fine at even below -20°C (increasingly more unreliably the lower you go), doing so is somewhat harmful for the engine. (Also, by heating the engine fluids you can also blow some warmer air into the cabin to prevent the windows from frosting when you get inside – not to mention the added comfort.) Actual battery warmers are much rarer I think, but that isn't often an issue as long as you keep your battery well charged (and obviously have a more capable battery to begin with). The usual recommendation is to start using the block heater even before temperature gets below freezing (for convenience reasons not many people do so).
isoskeles 9y ago
They could have pointed out the chargers on these cars. I’ve seen some that mimic a fuel pump and gas cap (implying there is a gas tank) even though that is all unnecessary.
- gowld 9y ago
  Why would you not need a port cover? Electric cars are charged by plugs to connect the electric line, same as how gas cars are charged by plugs to connect the gas line.
mikeash 9y ago
I'm pretty sure the radiator you need for an EV is much smaller. You need cooling, but not a whole lot. The cooling needs are similar to what you need for cooling the cabin, so the radiator will be similar to a normal car's AC radiator. The intake is just a small gap between the hood and the front of the car, not the giant grille most cars have.
Retric 9y ago
IC car radiators are limited by their working fluid to 100C before massive problems show up and in practical terms much lower temperatures. On the other hand electric motors can safely operate at over 100C minimizing the differences. However, while IC's produce vastly more waste heat much of it is simply dumped into the exhaust system which can in get hot enough to glow. ex: https://imgur.com/gallery/J7oNY https://imgur.com/gallery/J7oNY Both electric an IC cars need radiators for their AC system. Electric car batteries produce minimal heat in use, but while charging may produce significant heat. So, it's really quick charging stations and the AC system that causes minimal radiator needs.
- cc439 9y ago
  Automotive cooling systems have been designed to operate in excess of 100C for decades now. The system is designed to pressurize the coolant to raise the boiling point by as much as 25C/45F. The radiator cap acts as a pressure release valve and most are typically designed to blow at 15psi above atmospheric pressure. You also have the intended working temperature of ICE and eletric powerplants inverted. While an ICE's cooling system is designed to keep maximum coolant temperature around 110-115F, the internal components are designed to operate far in excess of that temperature. Exhaust valves, for example, are designed to operate indefinitely at temperatures exceeding 700C with the valves of high performance engines nudging 900C. Electric motors on the other hand, rapidly lose efficiency as operating temperature increases.
  - Retric 9y ago
    Radiator sizing only cares about the working fluid temperature, temperatures past that point are irrelevant. Anyway, remember failure point != safe operation. 50/50 antifrease mixture generally boils at 220f at 1atm. As you say assuming nothing is wrong up to 265f is possible to maintain, but operating temperatures are generally kept below the boiling point for several very good reasons. Critically, the engine should operate even if the cooling system has a minor leak as long as it's working fluid is topped off.
    - sudojudo 9y ago
woobar 9y ago
Even ICE cars use oversized grilles mostly as decoration. Look at the Ford Focus (http://i.imgur.com/DEhSO19.jpg http://i.imgur.com/DEhSO19.jpg), actual vents could be much smaller.

grogenaut 9y ago

but why does it need the grille, if the radiators are low then the grill is in the wrong spot, no?

pySSK 9y ago
Yep. Look at Model 3 design. Low radiator grille: https://www.instagram.com/p/BamdM3clVU3/ https://www.instagram.com/p/BamdM3clVU3/
- tempestn 9y ago
  It's almost like the reverse of what the article is talking about. People expect electric cars to not need radiators, so they design the Teslas specifically to look different, even though in this way they're actually pretty similar to other cars!

taneq 9y ago

> Electric engines do indeed release a lot less waste heat than internal combustion engines, but they also can't tolerate nearly as high of temperatures. Eh? I thought both topped out around ~100 degrees C? Not that water cooling isn't a good idea for automotive electric drive motors.

tempestn 9y ago
Sorry, I guess I worded that poorly. In the electric case, it's specifically the batteries that need to be kept cooler. So while the whole system puts off less heat, at least the battery portion also withstands less, so still needs a significant radiator.
deleted 9y ago
[deleted]
giobox 9y ago
Rechargeable batteries of most designs are pretty heat sensitive. Too hot or too cold and the maximum range of the electric vehicle suffers. The drop off can be as high as 30% or so too, especially if you live somewhere with regular seasonal extreme temperatures. This is why as well as cooling systems, some EVs even heat the battery in the cold. The same thing affects Lithium Ion batteries in phones, cameras, laptops etc too.
- phyzome 9y ago
  Hah, sounds kind of like LED lights -- way less waste heat, way more sensitive to what heat there is.
- derefr 9y ago
  > This is why as well as cooling systems, some EVs even heat the battery in the cold. IC cars have that feature too, if you live somewhere like Saskatchewan. You need to plug the heater in at night (https://info.kaltire.com/wp-content/uploads/2015/03/Jan-6-PlugIn.jpg https://info.kaltire.com/wp-content/uploads/2015/03/Jan-6-Pl...) or the battery will be too cold to start the car in the morning.
  - YSFEJ4SWJUVU6 9y ago
    Block heaters are used in somewhat milder climates as well – even though a modern ICE will start quite fine at even below -20°C (increasingly more unreliably the lower you go), doing so is somewhat harmful for the engine. (Also, by heating the engine fluids you can also blow some warmer air into the cabin to prevent the windows from frosting when you get inside – not to mention the added comfort.) Actual battery warmers are much rarer I think, but that isn't often an issue as long as you keep your battery well charged (and obviously have a more capable battery to begin with). The usual recommendation is to start using the block heater even before temperature gets below freezing (for convenience reasons not many people do so).

isoskeles 9y ago

They could have pointed out the chargers on these cars. I’ve seen some that mimic a fuel pump and gas cap (implying there is a gas tank) even though that is all unnecessary.

gowld 9y ago
Why would you not need a port cover? Electric cars are charged by plugs to connect the electric line, same as how gas cars are charged by plugs to connect the gas line.

mikeash 9y ago

I'm pretty sure the radiator you need for an EV is much smaller. You need cooling, but not a whole lot. The cooling needs are similar to what you need for cooling the cabin, so the radiator will be similar to a normal car's AC radiator. The intake is just a small gap between the hood and the front of the car, not the giant grille most cars have.

Retric 9y ago

IC car radiators are limited by their working fluid to 100C before massive problems show up and in practical terms much lower temperatures. On the other hand electric motors can safely operate at over 100C minimizing the differences. However, while IC's produce vastly more waste heat much of it is simply dumped into the exhaust system which can in get hot enough to glow. ex: https://imgur.com/gallery/J7oNY https://imgur.com/gallery/J7oNY Both electric an IC cars need radiators for their AC system. Electric car batteries produce minimal heat in use, but while charging may produce significant heat. So, it's really quick charging stations and the AC system that causes minimal radiator needs.

cc439 9y ago
Automotive cooling systems have been designed to operate in excess of 100C for decades now. The system is designed to pressurize the coolant to raise the boiling point by as much as 25C/45F. The radiator cap acts as a pressure release valve and most are typically designed to blow at 15psi above atmospheric pressure. You also have the intended working temperature of ICE and eletric powerplants inverted. While an ICE's cooling system is designed to keep maximum coolant temperature around 110-115F, the internal components are designed to operate far in excess of that temperature. Exhaust valves, for example, are designed to operate indefinitely at temperatures exceeding 700C with the valves of high performance engines nudging 900C. Electric motors on the other hand, rapidly lose efficiency as operating temperature increases.
- Retric 9y ago
  Radiator sizing only cares about the working fluid temperature, temperatures past that point are irrelevant. Anyway, remember failure point != safe operation. 50/50 antifrease mixture generally boils at 220f at 1atm. As you say assuming nothing is wrong up to 265f is possible to maintain, but operating temperatures are generally kept below the boiling point for several very good reasons. Critically, the engine should operate even if the cooling system has a minor leak as long as it's working fluid is topped off.
  - sudojudo 9y ago

woobar 9y ago

Even ICE cars use oversized grilles mostly as decoration. Look at the Ford Focus (http://i.imgur.com/DEhSO19.jpg http://i.imgur.com/DEhSO19.jpg), actual vents could be much smaller.