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I've read a few posts/threads on here about the high cost of replacing battery coolant a few years down the road, usually running into several hundred pounds. Reminds me of the need to change cam belts every 40/50,000 miles, adding a tidy sum to annual servicing costs.

I've had my Leaf almost four years now and am looking around at alternatives with a longer range, but have to admit the prospect of forking out £4-500 to have the coolant changed is more than a little off-putting.

How are people dealing with that possibility? Just grinning and bearing it, or shocked to suddenly find out how expensive the coolant change is? Are all battery cooled models similarly expensive. I read on one of the forums here that someone pulled out of buying a car two days before delivery when they found out the cost.
 

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2020 VW ID3 Life 58kWh
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I think it's a bit different to a cam belt, if a cam belt goes best case you need a tow to the nearest garage, worst case you need a flatbed from a scrapper!

If the HV coolant system failed on an EV then I would presume it would start to behave like a passively cooled EV such as the Leaf so rapid charging speed maybe reduced and the rate of battery degradation could increase but I'd imagine the car would be usable and the owner could ignore the problem if they so wished but I'd think it would be best to keep to any service schedule as a working cooling system could improve battery life by 50% or more so its worth a few hundred quid every 4-5 years.
 

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I think that’s unlikely, though this is speculation, I’d expect a system designed with active system will need that. You won’t get much passive cooling so potential hotspots and that would probably lead to an HV shutdown, at least one would hope so.

That said a sudden and catastrophic failure is less likely than with a cambelt.
 

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It'll be a bit like brake fluid ... you should change it, but it'll be a long time after the 'best before' date before it becomes an actual problem.

The main issue is that if the (battery) warranty is still valid then it may not be after you skip the fluid change.
You feel lucky, punk? :)
 

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The suggestion that a cambelt change is a money making exercise is hilarious.

Might I suggest a bus pass or a short term rental.
 

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The difference here is that cam belts do wear out and do break, unpredictably at some point after their recommended lifetime, and failure usually results in catastrophic damage to the engine that is expensive or uneconomic to repair depending on the design of the engine plus a little bit of luck. So there is a genuine reason to replace them on a schedule. If you don't, you're rolling a dice for sudden and unexpected failure of the engine.

Regular and expensive coolant changes on EV's (of the sort Kia and Hyundai are now demanding) is to put it frankly, BS.

Coolant is changed every few years in ICE vehicles because it is in a very harsh environment. It runs at up to 110C, passes through an engine with mixed metals that are in direct contact (often cast iron and aluminium) which can cause galvanic corrosion, and there is the possibility of oil or combustion product contamination. It has sacrificial corrosion inhibitors to help avoid galvanic corrosion in an engine and these are consumed over time. In short it is heavily stressed, and leads a hard life.

Coolant in an EV leads a much easier life. Something that needs to be remembered is that all EV's have a cooling system regardless of whether the battery is liquid cooled.

It's pretty much universal that an EV will have a regular radiator at the front with fairly standard coolant similar to or identical to that used in ICE vehicles, this is pumped through the motor(s), the drive inverter and onboard charger even on an EV like a Leaf with no battery cooling.

An EV with liquid cooled battery has all the same plus the coolant is pumped through channels or cooling plates in the battery enclosure as well.

Typical working temperature is only 20-40C perhaps reaching 50-60C under very extreme conditions vs 90-110C in a combustion engine where even a gently driven car is going to be running the coolant at 90C under 1.2 bars pressure once the engine is warmed up.

There is no mix of cast iron and aluminium in direct contact with each other with coolant flowing through them like there is on an ICE vehicle so corrosion inhibitors are not consumed.

There is no risk of combustion products or oil contaminating the coolant. In short the coolant leads a very easy life compared to a combustion car. So easy that the grill on most EV's is largely blocked off and the cooling pump on many EV's only runs intermittently as needed.

As an interesting data point, the service schedule for the i-Miev/Ion/C-Zero only has two consumable items scheduled for replacement (outside of brake pads, brake fluid etc) and that's gearbox oil, the motor coolant and heater fluid. (Which are both the same but on separate circuits)

They recommend changing the gearbox oil every 52,500 miles and the motor coolant and heater fluid every 240 months. Yes that's not a typo - the service schedule for the coolant is once every 20 years....so, longer than the likely service life of the car... :ROFLMAO:

Kia and Hyundai now claim theirs has to be replaced every few years at great expense. Sorry, but I'm just not buying the need for that... check for leaks and check the level, sure.

It's just a gravy stream to give the service departments something to do that they can charge for while holding the battery warranty to ransom.
 

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I've just checked MGs website for their EVs service scheduled it just says coolant at 4 years or 60k but it doesn't say if that is for the battery the motor or even the air con 🤷‍♂️
 

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I've just checked MGs website for their EVs service scheduled it just says coolant at 4 years or 60k but it doesn't say if that is for the battery the motor or even the air con 🤷‍♂️
Aircon doesn't use "coolant", and the battery and motor will be sharing the same cooling system and radiator even if they have valves to reconfigure it into different modes in different operating conditions. (As Tesla's do for example)
 

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Got confused as I saw coolant (con) in an ICE service schedule and my brain read air con!

I think MG has different coolants for the motor and the battery it certainly has two tanks to put coolant into one for the battery and another for drive system.
 

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Kia and Hyundai now claim theirs has to be replaced every few years at great expense. Sorry, but I'm just not buying the need for that... check for leaks and check the level, sure.
Hyundai have only changed the requirements for the latest cars because they now use a different coolant. I think the earlier ones use a similar coolant to ICE with a long life and low cost.
The new Konas now use a non-conductive (and perhaps less damaging to the environment) coolant which is expensive and has a shorter working life.
There is obviously some advantage in not using a conductive coolant inside a 400V battery since the effects of a leak may become very apparent long before you get round to an annual check for such.
 

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Coolant in an EV leads a much easier life.
To an extent I agree with your argument, but in some ways the lower temperatures are a problem as they are with brake fluid in comparison to ICE coolants. The issue is water getting into the system and contaminating the fluid - at least in ICE coolants they get hot enough to boil it off.
The main issue is that if the (battery) warranty is still valid then it may not be after you skip the fluid change.
You feel lucky, punk? :)
Exactly. Most people flip their cars regularly enough that they are unlikely to be the victim. So it is another thing to check when buying a used EV, something that the "average" person will miss. No wonder leasing is so popular. :unsure:
 

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What are you talking about?

Engine coolant always has water in it. If it all boiled off you’d have a problem.
Good question, if I'm confusing oil and water things are getting bad! :p :devilish:
 

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I've read a few posts/threads on here about the high cost of replacing battery coolant a few years down the road, usually running into several hundred pounds. Reminds me of the need to change cam belts every 40/50,000 miles, adding a tidy sum to annual servicing costs.

I've had my Leaf almost four years now and am looking around at alternatives with a longer range, but have to admit the prospect of forking out £4-500 to have the coolant changed is more than a little off-putting.

How are people dealing with that possibility? Just grinning and bearing it, or shocked to suddenly find out how expensive the coolant change is? Are all battery cooled models similarly expensive. I read on one of the forums here that someone pulled out of buying a car two days before delivery when they found out the cost.
Which brand and model of EV are you actually considering. If it's just a vague general concern, do a bit of research You will find that battery cooling systems are not all the same. Also consider that battery warranty periods differ between brands. If it's a brand with a long warranty and it's a condition of the warranty that the coolant is changed, consider purchase upfront of an all inclusive servicing deal.
 

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Hyundai have only changed the requirements for the latest cars because they now use a different coolant. I think the earlier ones use a similar coolant to ICE with a long life and low cost.
The new Konas now use a non-conductive (and perhaps less damaging to the environment) coolant which is expensive and has a shorter working life.
There is obviously some advantage in not using a conductive coolant inside a 400V battery since the effects of a leak may become very apparent long before you get round to an annual check for such.
Take the non conductive label with a huge grain of salt.

The Hyundai coolants are still water based.

True non conductive coolants do exist, eg 3Ms coolants suitable for submerged cooling of electronics but these are exotic fluids and so far no vehicle OEMs are using them.
 
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