**Assuming the insulation tester is using AC** and not being affected by the DC from the battery, there is no point isolating and testing insulation on individual batteries, as all leakage will be in parallel, and any resistance on a particular cell will be teh same or higher than that of the pack as a whole, though it may help in locating where leakage is occurring.
It was great to see the "inside" of the MG battery Pack, and to also watch the examination of each Cell and the Insulation Testing. However, I am no expert, but thought that anything over 20M Ohms would be OK. My biggest concern was those Plastic Unions (inside of the battery Pack), and the Coolant that flowed through. I honestly think that the Inlet & Outlet should have (perhaps) undergone some Pressure Testing, and I am thinking that 1 Bar should be sufficient - since this is a low-Pressure System. The dampness found inside that battery Pack will definitely shorten the Battery Life, as cathodic corrosion takes over. Many EVs will need to drive on flooded roads - and survive with their Battery Packs potentially fully immersed! Thankfully, I own a '71 EV Beetle, with both Battery Packs way up high, at 750mm above Road Surface level. At least the Owner of that MGEV can see the work entailed in getting down to the problem. Greetings from Australia.
Great video - thanks. No need to measure insulation resistance to both polarity terminals on each module as they are connected via the internal cells. Also personally I would use rubber gloves when working with an insulation tester that generates over 500 volts.
It proves to me that you and your team are the trailblazers in fixing EV batteries, dispelling the myth that, you must purchase a complete unit. In a few years time, many motor shops like yours will be springing up offering to repair defective EV cells. I did wonder if the pink pads under each 22.2 volt cell had reacted to water ingress. iPads and iPhones have a tell tail moisture sensor similar to what you have there. I would have been tempted to lift another cell from the next bank just for curiosity. It’s a shame that any of the internals can’t be purchased from MG directly. The underbody protection was almost none existing. That’s going back to the days when manufacturers didn’t even bother with any type of rust protection. A very interesting watch! MG should be ashamed of the standard build quality in my opinion.
All too easy to say what do you expect from China crap, but looks not too bad to me and as you say the Nissan leaf was similar, but OK if you want spend twice as much on an Audi or BMW go ahead.The fact that you have opened up Audi and other european makes show they also have problems. Thanks for showing this repair, it will become a growth industry, you are in the right place
Great video - thank you. The shocking thing to me was that a front spring had broken on a 2019 car. It cements my view that I wouldn't touch an MG with a bargepole. I've seen similar build quality problems with Tesla. Are Volvo any better because they, too, are Chinese built these days. I currently drive a Skoda and, so far, it's been fault free.
One EV to avoid: I test drove one, managed to crash its software 3 times on the road. Sure they fixed that but overall it is designed to be dumped past warranty. Lucky you managed to save this one.
Great video Gary. Bit of a poor design and quality control really but good for your business i suppose !! The Insulation tester looks a good bit of kit
I've got the same issue except mine isn't intermittent and I cannot clear the fault using my Autel maxisys ultra EV although I cannot test the HV pack as Autel don't have mg on their list....
Thank you for this insight. Good to know. So this battery is non-serviceable in the sense of that internal parts cannot be ordered. Apparently there's no moisture ingress sensor and the seal fails before the battery itself is EOL. I think I'd also inspect the BMS boards and cabling for moisture damage. Or at least, to see if I'd be happy with the BMS moisture protection. For peace of mind. You know. I mean, they failed to get the sealing right. Who knows what else could go wrong with that battery.
**Assuming the insulation tester is using AC** and not being affected by the DC from the battery, there is no point isolating and testing insulation on individual batteries, as all leakage will be in parallel, and any resistance on a particular cell will be teh same or higher than that of the pack as a whole, though it may help in locating where leakage is occurring.
..although it might be useful in finding the location of any leaks/damage
It was great to see the "inside" of the MG battery Pack, and to also watch the examination of each Cell and the Insulation Testing. However, I am no expert, but thought that anything over 20M Ohms would be OK. My biggest concern was those Plastic Unions (inside of the battery Pack), and the Coolant that flowed through. I honestly think that the Inlet & Outlet should have (perhaps) undergone some Pressure Testing, and I am thinking that 1 Bar should be sufficient - since this is a low-Pressure System. The dampness found inside that battery Pack will definitely shorten the Battery Life, as cathodic corrosion takes over. Many EVs will need to drive on flooded roads - and survive with their Battery Packs potentially fully immersed! Thankfully, I own a '71 EV Beetle, with both Battery Packs way up high, at 750mm above Road Surface level. At least the Owner of that MGEV can see the work entailed in getting down to the problem. Greetings from Australia.
Thanks for this. I have a ZS EV and good to see things can be sorted if need be. I have little faith in MG themselves.
Great video - thanks. No need to measure insulation resistance to both polarity terminals on each module as they are connected via the internal cells. Also personally I would use rubber gloves when working with an insulation tester that generates over 500 volts.
It proves to me that you and your team are the trailblazers in fixing EV batteries, dispelling the myth that, you must purchase a complete unit. In a few years time, many motor shops like yours will be springing up offering to repair defective EV cells.
I did wonder if the pink pads under each 22.2 volt cell had reacted to water ingress. iPads and iPhones have a tell tail moisture sensor similar to what you have there. I would have been tempted to lift another cell from the next bank just for curiosity. It’s a shame that any of the internals can’t be purchased from MG directly. The underbody protection was almost none existing. That’s going back to the days when manufacturers didn’t even bother with any type of rust protection. A very interesting watch! MG should be ashamed of the standard build quality in my opinion.
The battery is partitioned and there was no evidence of moisture in the other rows
Great video thanks for taking the time
Great video as always ❤
What a great video, thanks for sharing
good video. thanks
All too easy to say what do you expect from China crap, but looks not too bad to me and as you say the Nissan leaf was similar, but OK if you want spend twice as much on an Audi or BMW go ahead.The fact that you have opened up Audi and other european makes show they also have problems.
Thanks for showing this repair, it will become a growth industry, you are in the right place
Great video - thank you. The shocking thing to me was that a front spring had broken on a 2019 car. It cements my view that I wouldn't touch an MG with a bargepole. I've seen similar build quality problems with Tesla. Are Volvo any better because they, too, are Chinese built these days. I currently drive a Skoda and, so far, it's been fault free.
early spring failures are sadly quite common
One EV to avoid: I test drove one, managed to crash its software 3 times on the road. Sure they fixed that but overall it is designed to be dumped past warranty. Lucky you managed to save this one.
Great video Gary. Bit of a poor design and quality control really but good for your business i suppose !! The Insulation tester looks a good bit of kit
Yeh build quality ain’t great, the insulation tester is mustard btw
1/4 1000v socket set Laser Tools 6145
Those gloves look like they need replacing! Good video!
They’re fine, they get dirty if you use them you know
@@intelligentauto737 national grid guys wear leather over the rubber to protect them a little
@@itsmyview2024 national grid guys are working on 25000V not 400v
another quality Chinese flame thrower battery pack. stay safe ..
Don't the high voltage battery have a 7 year warranty?
Upto 100k this is at 110k
I've got the same issue except mine isn't intermittent and I cannot clear the fault using my Autel maxisys ultra EV although I cannot test the HV pack as Autel don't have mg on their list....
@@davidcorlett2082 give us a call and book it in, we can identify the issue
Any chance the car had been in RTC to affect the battery seal?
No accident history
Thank you for this insight. Good to know. So this battery is non-serviceable in the sense of that internal parts cannot be ordered. Apparently there's no moisture ingress sensor and the seal fails before the battery itself is EOL.
I think I'd also inspect the BMS boards and cabling for moisture damage. Or at least, to see if I'd be happy with the BMS moisture protection. For peace of mind. You know. I mean, they failed to get the sealing right. Who knows what else could go wrong with that battery.
Great video thanks for sharing. Did you re use the original gasket or apply another kind of sealant to the battery cover?
I used a waterproof chemical sealant called CT1
Great video, but you didn't check that the bottom of the batteries were dry before refitting!
I did, they were all completely dry before refitting
Plastic coolant pipes inside a hv battery 😂 not asking for trouble ,much
You wouldn’t want copper ones would ya