Depending on usage a standard car battery can be dead in as little as 100 deep discharge cycles, EFB/AGM a bit better, some lithium types can take in excess of 3000 under similar use.
Dead Nissan Leaf help!
- Thread starter katie279
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Depending on usage a standard car battery can be dead in as little as 100 deep discharge cycles, EFB/AGM a bit better, some lithium types can take in excess of 3000 under similar use.
Soldato
Tesla Roadster did that an its bricked the main battery after long period.
No one else thought of it until you came along of course...
Soldato
Tesla are moving away from 12v. I don't think it'll be that long before most also make the same shift.
www.electronicdesign.com
48-V Systems: What You Need to Know as Automakers Say Goodbye to 12 V
Today, 48-V power systems are already helping improve the efficiency and performance of ICE and mild hybrid vehicles, but they will become an essential technology for tomorrow...
www.electronicdesign.com
Soldato
The need to make sure the pedals dont fall off that car first.
Same difference, Seperate low voltage bus. The Leaf battery may be dead now after a deep discharge so thankfully as its just a small 12V lead acid its a pretty cheap replacement.
Same difference, Seperate low voltage bus. The Leaf battery may be dead now after a deep discharge so thankfully as its just a small 12V lead acid its a pretty cheap replacement.
Soldato
This is how most modern cars work with completely flat batteries, when they get that low, all the electronics shut off, and won’t turn back on unless it’s got sufficient voltage, so ‘jump starting’ from another 12v battery is required.o
Same happened to my daughter with her boyfriend, he had a VW Up 1.0, sat in it for hours, flattened the battery and everything was dead, I popped out to help, couldn’t bump start it since the electronics would not wake up.. I then realised the ID.3 I was in had the exact same battery as his Up, so jump started his Up off the ID.3 which worked.. It was funny for the opposite reason, an EV jump starting an ICE car!
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Soldato
On paper, 12v/48v wouldn't make any difference to the thread, if the requirement is to have a backup LV battery for safety systems then you'd need a 48v battery alongside the main HV battery.. that would still be able to be flattened..Tesla are moving away from 12v. I don't think it'll be that long before most also make the same shift.
48-V Systems: What You Need to Know as Automakers Say Goodbye to 12 V
Today, 48-V power systems are already helping improve the efficiency and performance of ICE and mild hybrid vehicles, but they will become an essential technology for tomorrow...
However, reading that article, it seems they've taken the leap to remove the LV battery entirely "The vehicle's 48 V is derived from the vehicle's primary 400/800-V battery and then sent to 12-V power converters located close to the load points"..
Hmm.. they could have done that now, derived the 12v from the main HV battery, but they chose not to for (presumably) safety reasons..
From 2022 onwards, Model Y/Model 3 have a 12v li-ion battery (went alongside the AMD Ryzen processor change).. however, since it doesn't need to crank an engine, it's not that large, so looks <£500 new, some are saying the Model S/X Li-ion battery from Tesla was $200..
Soldato
I added that in response to the post that was surprised 12v batteries haven't evolved in the world of EVs.
Keeping a separate low voltage battery seems like the way things should be, and will continue to be, even in EVs.
Soldato
Every day’s a school day! Thanks.
Soldato
Basic cheap and manage hotel loads, nothing to evolve too much. Premium brands will step toward lithium that’s for sure.
Caporegime
Stick the battery in an ICE car bump/jump start it then use the alternator to charge it back up 
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Soldato
Nah DCDC does a much cleaner job in the HV battery 
.. for colder climates not sure lithiums are so good for high wedges of cranking current ...
the replacement cost of them alone per above, for 2nd owner versus agm/lead yikes; can't lead/agm be recycled just as well, too, so no higher environmental cost.
For an EV you don't need cranking current (though some hybrid, etc. type systems are another matter).
You can get the appropriate battery for £200-300 though that is a fair bit more than the equivalent lead acid, though the OE ones are often priced in the £600-1000! range.
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