Flat Battery

Steve W

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Doncaster UK
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ZS EV Trophy LR
I`m thinking of buying one of those portable 12V battery jump starters as I`ve heard that the 12V battery on EVs have a tendancy to go flat when left. (My car will soon be left at an airport for two weeks. )
Does anybody have any recomendations?
Also, very silly question, but can you still unlock the car if the 12V battery is flat? I don't fancy leaving it for two weeks at the airport unlocked.
 
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This doesn't happen as a matter of course so I wouldn't worry too much if you aren't already experiencing problems. You can still open the driver door with a key if the 12V battery is flat.
Having a backup is still a good idea though and there are many existing threads giving recommendations. I have one myself but I've never needed to use it!
 
I`m thinking of buying one of those portable 12V battery jump starters as I`ve heard that the 12V battery on EVs have a tendancy to go flat when left. (My car will soon be left at an airport for two weeks. )
Does anybody have any recomendations?
Also, very silly question, but can you still unlock the car if the 12V battery is flat? I don't fancy leaving it for two weeks at the airport unlocked.


Post in thread 'What have you bought for your Xpower this week ?' https://www.mgevs.com/threads/what-have-you-bought-for-your-xpower-this-week.15680/post-298745


And where it is stored.

Post in thread 'What have you bought for your Xpower this week ?' https://www.mgevs.com/threads/what-have-you-bought-for-your-xpower-this-week.15680/post-306856
 
I`m thinking of buying one of those portable 12V battery jump starters as I`ve heard that the 12V battery on EVs have a tendancy to go flat when left. (My car will soon be left at an airport for two weeks. )
Does anybody have any recomendations?
Also, very silly question, but can you still unlock the car if the 12V battery is flat? I don't fancy leaving it for two weeks at the airport unlocked.

before you go to the airport, top up the car to 100% and you have nothing to worry about. I left mine for a week with 70% charge and that's how I found it when we got back. Main battery will top up 12V battery as needed.
 
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before you go to the airport, top up the car to 100% and you have nothing to worry about. I left mine for a week with 70% charge and that's how I found it when we got back. Main battery will top up 12v battery as needed.

Unless the 12V is dicky or on the way out which is what has happened to folk.

What is supposed to happen and what does indeed happen.......

Belt N Braces and all that.
 
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Unless the 12v is dicky or on the way out which is what has happened to folk.

What is suppose to happen and what does indeed happen.......

Belt N Braces and all that.

That's why I also got one of those 12V jump starter power pack from AliExpress ?. Just need to remember to top it up from time to time ...
First sign of a dodgy 12V battery - get a new one immediately !
 
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The problem with EVs are that there is little warning the the 12V is going weak, unless you constantly monitor the app, which of course could make it worse. In an ICE you get some advanced warning with the starter motor sounding weak and labouring. Unless you know the cut off point in voltage terms where it is too weak to start the system , its hard to know when to change the battery for a new one, but easy to get caught out by a cold spell when the voltage can drop below the minimum required, or where even the slightest unforseen battery drain which has the same effect. A jumper pack is useful , but in a way its shutting the gate after the horse has bolted. Whilst its still valid a regular check directly on the battery terminals ( car off ) with a multimeter especially as the weather changes is the way to compare its day to day (weekly) state of charge
Unless of course someone else has worked out the symptoms of when the 12V is starting to fail by the way the car reacts, maybe slow weak sounding door locks?
 
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I`m thinking of buying one of those portable 12V battery jump starters as I`ve heard that the 12V battery on EVs have a tendancy to go flat when left. (My car will soon be left at an airport for two weeks. )
Does anybody have any recomendations?
Also, very silly question, but can you still unlock the car if the 12V battery is flat? I don't fancy leaving it for two weeks at the airport unlocked.
I left my ZS trophy at Stansted for three weeks last December.
Started with no probs.
 
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