All - Water and EVs

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Tue 13 Jul 2021 15:31
All - Water and EVs - sammy1

I was wondering having seen the flash flooding in parts of the country would you even contemplate taking your EV even through a shallow flood? How well are the batteries protected from water ingress?

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Tue 13 Jul 2021 15:47
All - Water and EVs - Andrew-T

I would assume that even the most dim-witted designer might have thought of that more-than-possibility. Fords (the wet ones) or M-ways in a downpour are more likely occurrences to think about. And of course conventional cars have batteries (a bit higher, admittedly) which might get shorted by total immersion.

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Tue 13 Jul 2021 18:23
All - Water and EVs - galileo

I would assume that even the most dim-witted designer might have thought of that more-than-possibility. Fords (the wet ones) or M-ways in a downpour are more likely occurrences to think about. And of course conventional cars have batteries (a bit higher, admittedly) which might get shorted by total immersion.

In fresh water a 12 volt battery is unlikely to be seriously 'shorted'. ECU is usually lower down and more vulnerable. Many cars have electronic parts under seats, which will also suffer if immersed.

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Tue 13 Jul 2021 15:53
All - Water and EVs - Bromptonaut

I was wondering having seen the flash flooding in parts of the country would you even contemplate taking your EV even through a shallow flood? How well are the batteries protected from water ingress?

Much better than the air intake on an ICE car.

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Tue 13 Jul 2021 17:11
All - Water and EVs - sammy1

So are you saying that EV batteries are contained in a completely water tight compartment. Is the electric motor also protected from flood water? The batteries on EVs are slung much lower than ICE and air intakes on ICE are high up. The exhaust might be a problem but not if you drive through low water correctly

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Tue 13 Jul 2021 17:23
All - Water and EVs - corax

air intakes on ICE are high up.

Not always, they have been sited in some very illogical places over the years.

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Tue 13 Jul 2021 17:50
All - Water and EVs - Bromptonaut

So are you saying that EV batteries are contained in a completely water tight compartment. Is the electric motor also protected from flood water? The batteries on EVs are slung much lower than ICE and air intakes on ICE are high up. The exhaust might be a problem but not if you drive through low water correctly

I think we're saying that the designers will have thought through protecting critical circuitry and components from water under normal driving conditions. By that I mean downpours, fords and flood water below (say) the door cills.

Every time there are floods there's a bit of spectator sport watching ICE cars that stall or float in a flood. A few unlucky individuals submerge the air intake and bend a con-rod or two in a vain attempt to defy physics and compress water.

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Tue 13 Jul 2021 19:25
All - Water and EVs - Brit_in_Germany

Teslas have liquid cooled battery units so I would hope that these are sealed units.

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Wed 14 Jul 2021 11:25
All - Water and EVs - Engineer Andy

Teslas have liquid cooled battery units so I would hope that these are sealed units.

True, but seals will eventually fail, as they always do on ICE cars. The coolant medium would then be susceptible to contamination if the car owner regularly took the car through deep flooded sections of road, fords, et, which would obviously not do the cooling system or batteries any good, from both a cooling or corrosion pov.

I would hope, however, that the seals where the coolant pipes and electrical/data cabling/connections go into/out of the battery pack area and between packs are accessible for inspection as part of regular maintenance.

Not sure if I'm at crossed purposes here, but I suspect the liquid cooling just means 'similar to a car radiator' (or how some overclocked computer processors are cooled in a similar manner), not the battery modules themselves immersed in a liquid cooling medium. I could be wrong on that, and if so would be interested to see how the tech works. Previous gen EV battery cooling (e.g. the gen-1 Leaf) was air cooled, and has been shown to not be up to the task, though mainly in hot countries.

Apologies if that wasn't the case - it was more if others reading your comments misconstrued it as meaning the Tesla batteries were already immersed in a liquid coolant.

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Tue 13 Jul 2021 22:20
All - Water and EVs - FoxyJukebox
Am I being stupid-surely electric cars don’t have exhaust pipes?
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Tue 13 Jul 2021 23:27
All - Water and EVs - focussed

I was wondering having seen the flash flooding in parts of the country would you even contemplate taking your EV even through a shallow flood? How well are the batteries protected from water ingress?

Much better than the air intake on an ICE car.

Funny!-I don't recall any petrol or diesel powered vehicle that has the engine air inlet under the floor!

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Wed 14 Jul 2021 07:02
All - Water and EVs - Bromptonaut

Funny!-I don't recall any petrol or diesel powered vehicle that has the engine air inlet under the floor!

The question wasn't where were the batteries situated but how well protected they might be.

Plenty of cars have the intake low down and towards the front. That's why hydro locking engines is a known issue driving through floods.

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Wed 14 Jul 2021 20:22
All - Water and EVs - Sofa Spud

No but some have the intake down behind the front bumper. If they take in water then it's probably a new engine (bent con-rods because water won't compress). I know this has actually happened to some cars. I'm amazed to think any car designer would think to put the air intake down behind the front bumper, putting the engine at risk in moderate flooding.

Edited by Sofa Spud on 14/07/2021 at 20:24

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Tue 13 Jul 2021 18:29
All - Water and EVs - mcb100
According to Jaguar, the I Pace has the same wading depth as a Land Rover Defender, and I’d suspect it’d be door seals that would succumb first. Or it’d just start to float, which is the usual limit on wading depth. A Nissan LEAF apparently has a 700mm wading depth.
Some quick reading around shows that they are IP67 or 68 equivalent for the electrical components.

Edited by mcb100 on 13/07/2021 at 18:33

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Tue 13 Jul 2021 21:28
All - Water and EVs - Metropolis.
The test will be when someone drives into a lake or river, are we going to see a whole load of dead fish?
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Tue 13 Jul 2021 22:25
All - Water and EVs - bathtub tom

Doesn't lithium react with water, similarly to sodium, but less violently? I understand firemen are instructed to let EVs burn and NOT put water on them.

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Tue 13 Jul 2021 22:46
All - Water and EVs - Bromptonaut

It does. It might even be more reactive. But then water's not much use against oil fires either.

Edited by Bromptonaut on 13/07/2021 at 22:50

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Tue 13 Jul 2021 23:09
All - Water and EVs - Andrew-T

But then water's not much use against oil fires either.

It would be, except that oil floats on it. If oil was denser, water would probably do OK. Alkali metals also float, but they react vigorously too.

Edited by Andrew-T on 13/07/2021 at 23:10

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Tue 13 Jul 2021 23:34
All - Water and EVs - focussed

As the common nominal pack voltages in current vehicles range from 100V-200V for hybrid/plug-in hybrid vehicles and 400V to 800V and higher for electric-only vehicles the last place you want to take your EV is to drive it through water!

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Wed 14 Jul 2021 06:56
All - Water and EVs - mcb100
This test driver is happy enough to do it -

youtu.be/Y9plRzRZ_PY
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Wed 14 Jul 2021 11:04
All - Water and EVs - ExA35Owner

Doesn't lithium react with water, similarly to sodium, but less violently? I understand firemen are instructed to let EVs burn and NOT put water on them.

However lithium metal is not used in the batteries. Instead a lithium compound is used.

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Wed 14 Jul 2021 14:32
All - Water and EVs - madf

What Happens When You Drown an Electric Car?

www.youtube.com/watch?v=ixXF72HFr5U

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Wed 14 Jul 2021 17:47
All - Water and EVs - Engineer Andy

What Happens When You Drown an Electric Car?

www.youtube.com/watch?v=ixXF72HFr5U

Very interesting video - thanks. It looks like - at least when the car is still reasonably new, that the battery system and motor(s) are indeed specifically designed to be highly tollerant to water ingress, becaue of the electric shock to people and animals also in the water - though I think only if the water doesn't breach that air hole in the boot (?).

I still suspect the seals will perish. Whether that is designed to last as long as the car, I don't know - it would be good if that was the case. The car in the video didn't look that old, and they didn't mention anything on that score.

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Wed 14 Jul 2021 20:55
All - Water and EVs - Xileno

I was thinking only earlier today that as the EV ages, seals etc. may get comprised. Maybe in the future EVs will need a safety check in this respect, maybe part of the MOT?

Also I wonder if anyone has any stats on the comparative cost difference in repairing an accident damaged EV compared to ICE? Maybe there is no significant difference although all the waterproofing must be quite expensive.

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Thu 15 Jul 2021 12:16
All - Water and EVs - Engineer Andy

I was thinking only earlier today that as the EV ages, seals etc. may get comprised. Maybe in the future EVs will need a safety check in this respect, maybe part of the MOT?

Especially (as the person in the video said) anyone wading in water near an EV would not appreciate the possibly fatal electric shock if the seals failed or the water got in over the breather hole, at least for that car.

Also I wonder if anyone has any stats on the comparative cost difference in repairing an accident damaged EV compared to ICE? Maybe there is no significant difference although all the waterproofing must be quite expensive.

I'm also wondering how many floods of that type can the seals/water proofing take before failure? Especially with floods in some areas becoming more commonplace for various reasons.

Some people in the future may not be able to obtain any vehicle insurance (or at an economic price*), especially if the push to change from ICE to EV in such a short space of time is followed. Once again pricing out of car ownership those elast able to afford to pay or move to an area less at risk.

* the video showed extensive interior works to dry and clean, including taking up the flooring/panels down to the bear metal, likely costing several £0000s, including the cost of temporary hire cars.

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Thu 15 Jul 2021 15:41
All - Water and EVs - Bromptonaut

Some people in the future may not be able to obtain any vehicle insurance (or at an economic price*), especially if the push to change from ICE to EV in such a short space of time is followed. Once again pricing out of car ownership those elast able to afford to pay or move to an area less at risk.

* the video showed extensive interior works to dry and clean, including taking up the flooring/panels down to the bear metal, likely costing several £0000s, including the cost of temporary hire cars.

I've not yet seen the whole YT video but I'm not convinced by the idea that somehow the car will, in the style of an electric eel, stun or kill those nearby.

30+ years ago there was a massive water main burst in Southampton Row in London. Completely flooded the underground car park of the Bedford Hotel. How different is the damage to the Zoe in the YT video to that of the wholly ICE Saab I saw being hauled out of that car park. Stinking brown water pouring from every orifice.

Even if its owner was somebody on the fringe of being priced out of car ownership the car was irredeemably wrecked.

If there are chinks in the armour of the move to electric vehicles than trying to make out that damage by flood is one of them is futile.

How about finding something that actually stacks up?

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Thu 15 Jul 2021 17:21
All - Water and EVs - Engineer Andy

Some people in the future may not be able to obtain any vehicle insurance (or at an economic price*), especially if the push to change from ICE to EV in such a short space of time is followed. Once again pricing out of car ownership those elast able to afford to pay or move to an area less at risk.

* the video showed extensive interior works to dry and clean, including taking up the flooring/panels down to the bear metal, likely costing several £0000s, including the cost of temporary hire cars.

I've not yet seen the whole YT video but I'm not convinced by the idea that somehow the car will, in the style of an electric eel, stun or kill those nearby.

30+ years ago there was a massive water main burst in Southampton Row in London. Completely flooded the underground car park of the Bedford Hotel. How different is the damage to the Zoe in the YT video to that of the wholly ICE Saab I saw being hauled out of that car park. Stinking brown water pouring from every orifice.

Even if its owner was somebody on the fringe of being priced out of car ownership the car was irredeemably wrecked.

If there are chinks in the armour of the move to electric vehicles than trying to make out that damage by flood is one of them is futile.

How about finding something that actually stacks up?

I was just reporting on what the person said in the video - who appear to be a mechanic (but not trained in maintaining EVs [he was the one stripping the car down to dry it out[) who had obtained advice from others, including Renault.

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Thu 15 Jul 2021 18:09
All - Water and EVs - sammy1

My initial post was just about deciding whether to drive though even a low level flood in your EV.. When you see the way some drive through floods and the bow wave they create I think I would think twice about it. As regards floods whereby the interior is compromised as well most cars are a write off. I would not try any flood that was higher than the sills.

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Thu 15 Jul 2021 20:53
All - Water and EVs - alan1302

My initial post was just about deciding whether to drive though even a low level flood in your EV.. When you see the way some drive through floods and the bow wave they create I think I would think twice about it. As regards floods whereby the interior is compromised as well most cars are a write off. I would not try any flood that was higher than the sills.

Shouldn't drive through with any car really unless it's really necessary/emergency.

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