12V Battery Intelligent Charging?

[tarbat]

Anyone know what voltage the 12V battery needs to drop to before the Cyberstar charges it from the HV Traction battery? Over 2 days mine has now dropped to 11.8V, which seems low to me.

 

[Paulie68]

Anyone know what voltage the 12V battery needs to drop to before the Cyberstar charges it from the HV Traction battery? Over 2 days mine has now dropped to 11.8V, which seems low to me.

11.8V isn't just low, that's almost entirely flat. I wouldn't have expected the car to let it get anywhere near that low.

 

[tarbat]

Looks like it's charging now according to the app.

 

[Hubcaps]

Just checked mine 12.1V showing on app, got in car Had Ready light come up app went to 14.1 volt.
I did read it charges when plugged in, as you have shown, also it will charge from HV battery when required, not sure if it does that if it was left sitting for days/weeks.

 

[GranTurismoEra]

Can it last 2 weeks while youre on holiday?

 

[Green Salop Man]

Sounds like the same software issue that affects the MG5. No surprise really considering MG’s recent history on failing to deliver software that is fit for purpose.

 

[tarbat]

Sounds like the same software issue that affects the MG5.

What software issue on the MG5? Do you have any more details please.

 

[Green Salop Man]

A lot of MG5 owners had issues as the car failed to keep the 12V battery sufficiently charged. I believe there is a firmware update now for the MG5. To be fair to MG the same issue has occurred with other makes of EV such as Kia.

 

[tarbat]

A lot of MG5 owners had issues as the car failed to keep the 12v battery sufficiently charged.

The Cyberster is keeping the 12V battery charged okay, unlike some other makes.
My query was about what voltage level the battery should drop to before the Intelligent Charging starts. From what I can find out, 11.8V represents around 30% charge, so maybe that's an appropriate voltage. I wonder what other MGs do?

 

[tarbat]

I thought I'd check back to the first EV I had, a Fiat 500e La Prima in 2022. I had a BM2 battery monitor fitted on that car, and looking back at the recordings I see that it also used to drop to 11.8V whenever I interrogated the car using it's APP. Presumably interrogating the car from the APP causes it to turn on various systems on the car.

So I'm starting to think that this is maybe normal on EVs.

 

[Paulie68]

The Cyberster is keeping the 12V battery charged okay, unlike some other makes.
My query was about what voltage level the battery should drop to before the Intelligent Charging starts. From what I can find out, 11.8V represents around 30% charge, so maybe that's an appropriate voltage. I wonder what other MGs do?

It's dependent on temperature, but 11.8V is more like 20%. Hopefully the reporting of 11.8V or so is when powered up with some load, so it's really higher, as if a lead acid battery is constantly cycled that low it won't last very long, better to top them up at 40% or more.

 

[tarbat]

It's dependent on temperature, but 11.8v is more like 20%. Hopefully the reporting of 11.8v or so is when powered up with some load, so it's really higher, as if a lead acid battery is constantly cycled that low it won't last very long, better to top them up at 40% or more.

I've now measure the 12V battery voltage without using the APP (with a multimeter), and it read 12.4V.

 

[Jto]

Anyone know what voltage the 12V battery needs to drop to before the Cyberstar charges it from the HV Traction battery? Over 2 days mine has now dropped to 11.8V, which seems low to me.

I would get a 12v trickle charger on to the battery ASP get it back up over 13v

 

[cyberthai]

I "parked" my Cyberster for 2.5 month without triggle charger as it is said the main battery will triggle.
I can confirm it is correct. After 2.5 months the battery was at 12.3V and no problem to start to drive. After switching on for a couple of minutes it went up to 12.5 and 12.9V, seems all good.

 

[internet]

My 12V battery failed after having left the car for 4 weeks quickly after taking delivery. After getting it back to working condition, it kept on failing after short drives 3 times (unable to open car). After going through the battery test cycle, it still couldn't hold it's voltage and the dealer agreed it was a good idea to replace it. Might have been a bad battery. I hope it wasn't something else.