matija
Posts: 2
Joined: Sat Nov 11, 2017 10:48 am

measuring capacity loss through CanIon

Sat Nov 11, 2017 11:05 am

Greetings everyone,

I have recently noticed that cani0n is now showing the Ah value of our battery modules. This raises few questions.

What is the new value of our Yuasa LEV50 cells ? They are branded as 50Ah. I doubt cani0n would really show 50 in brand new car. But if it would that means I have lost nearly 30% as cani0n shows 35.25Ah for me.

Although 50Ah * 88 cells * 3.7 nominal voltage does return 16kWh value.

Does anyone know how to re-initiate reading of Ah in cani0n ? This measurement was done when battery was cold and not full (14°C, 82% SoC)

I've read a lot of how voltage works in those cells, how newer cars can get 0% soc at quite high voltage (like Malm getting it at 3.6V), while older packs could go near the 2.75V limit. How SoC loss is compensated with shrinking the "turtle range", etc.

So, perhaps new car would return 50Ah to cani0n. If that is true, perhaps with BMS allowing to discharge cells deeper and deeper as they age, actually represent almost no visible SoC loss to users ?

I would love to hear others opinion.



Image

Aerowhatt
Posts: 326
Joined: Wed Jan 28, 2015 1:52 pm
Location: Albuquerque NM

Re: measuring capacity loss through CanIon

Thu Nov 16, 2017 1:04 pm

It’s cool that the update is showing this info since EVbatmon is such a PIA.

That’s correct that Mitsu hid part of the battery capacity from us to basically eliminate any user sense of battery degradation. Brilliant really, since degradation is kind of steep at first and then slows. Basically if you use the car as intended (never seeing turtle or running down to the bone). You would never know from the dash that the capacity was slowly decreasing. In doing so they also make the battery last longer by designating the “bottom” above the actual bottom.

I don’t recall anyone with reading above 47 ah for these battery cells. Manufacturer specs are a slow discharge under ideal conditions. Certainly not what happens in an EV!

It looks to me like it is the “calibration charge” which returns this info to the system. The three dates shown on my canion read out, all coincide with trips to the mountains followed by an uninterrupted charge to 100%.

The history panes in canion can be a bit misleading since they are disconnected in time from the current summary list on the left of the screen.

Aerowhatt
2014 cool silver ES, acquired new 4/2015
2014 Labrador Black Pearl ES, acquired new 3/2016

Return to “Batteries and Battery Management”