Twizy battery SOH (state of health)


(pisoiu) #1

For those who like to play with CAN bus, according to some documentation from virtual BMS, the message ID 424 byte 6 indicates the health status of the battery. I read it in december last year, when I purchased my twizy (new) and it was 0x64, meaning 100 in decimal. Ok, new=100% health. I read it again few days ago after 6500km and the value is the same, 100.
Does anyone know what is the expected degradation rate of battery health status (depending on km I assume)? It seems strange that not even 1% dropped in 6500km. I am not complaining, I just want to determine if that indication is accurate or not. Is there any other way to make twizy indicate on the dash board the battery health status? The battery is mine, not rented, this is the reason for such interest.


(osbrook) #2

No idea how to get the reading, but my 6year old battery and 19000miles It’s certainly down on holding and supplying the same rate as new.

Must be getting close to 25% down.


(Normsthename) #3

How do you know that?
My Twizy is a 2012 model with 27, 000 miles on the clock.
I don’t think the battery has lost much so far.
It still charges upto 99% before the screen goes black.

Andy


(pisoiu) #4

So the display indication is actually a combination between SOC (state of charge) and SOH (state of health)? It does not go up to 100% as the SOH degrades? I don’t remember reading that into the manual but I will look again.


#5

100% on the screen when charging just means the battery is fully charged. If the batt is dead you’d still have 100% of … nothing !

All batt systems are like this. Your cell phone, my house remote system…