Why do you care? My plan is to do nothing. All that has to happen is the passage of time.
Budget Battery Capacity Readout
- Thread starter MrFixit
- Start date
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Thanks for the answer.
To answer your testy question, I was curious. Your methodology is consistent, so you have that going for you.
atlgwinnett
New Member
About 2 weeks ago my 2018 Clarity PHEV displayed a PowerSystems Failure code on the dashboard. The vehicle had about 94000 miles and 38.86KWH of battery capacity. Took it to the dealer. They measured 55% battery capacity and replaced the traction battery. I am now reading 54.98KWH of battery capacity.
During the first 4 years I had the car I fully charged and discharged the battery about 15 times per week, charging at home and work with a L2 charger.
During the first 4 years I had the car I fully charged and discharged the battery about 15 times per week, charging at home and work with a L2 charger.
David Towle
Well-Known Member
FYI the unit is ampere-hours not kw-hours. Why they use that instead of kw-hours I don't know but they do. A new Clarity is said to have a battery capacity of 17 kw-hours or 55 ampere-hours. Dividing those out gives a voltage of 310 volts, why that does not yield the system voltage of 350 volts I don't know that either.
My car is similar age and mileage and its just under 45 amp-hours
Nominal cell voltage is used in the formula. The Clarity has 2 battery banks, A and B, each with 84 cells in series. Each cell has a nominal voltage of 3.7V, which when multiplied by 84 gives us 310.8V.
Targeted cell charging voltage is ~4.09V, which gives us ~343V. Using the targeted voltage would give an inflated capacity rating in kWh’s. During operation, both charging and discharging, cell voltage will fluctuate from ~4.09 to as low as 3.0V. I don’t actually know the low voltage cutoff used by the BMS. It could be 3.2V. Regardless, using 3.2V, or anything less than the nominal voltage, would give us a deflated capacity rating in kWh’s.
Targeted cell charging voltage is ~4.09V, which gives us ~343V. Using the targeted voltage would give an inflated capacity rating in kWh’s. During operation, both charging and discharging, cell voltage will fluctuate from ~4.09 to as low as 3.0V. I don’t actually know the low voltage cutoff used by the BMS. It could be 3.2V. Regardless, using 3.2V, or anything less than the nominal voltage, would give us a deflated capacity rating in kWh’s.
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Did you notice any changes in the performance or operation of the vehicle after the code was displayed? Would it not allow operation in EV mode or not allow regen? Was acceleration impaired?
atlgwinnett
New Member
I don't know. The error code was displayed on my way to work. I drove 5 miles in bumper to bumper traffic, went to work, then the 3 miles to the dealer. I did not want the error code to clear itself. The dealer gave me a loaner car to use for a little over a week while the waited to receive the battery pack and installed it. Installation went smoothly. I did need to return the vehicle to the dealer for them to bleed the coolant loop. This wasn't a big deal since this is likely the first Clarity battery which they have replaced.
MFKilla
New Member
This PID is ok? Trying tp use it but has something wrong
MrFixit
Well-Known Member
You shouldn't have to be worried about low level protocols like PID's
Do not try to use Torque Pro...
This is all coded into Car Scanner
Follow these instructions:
https://clarity-phev.github.io/Battery-Capacity-Read/ELM_CarScanner_Instructions.pdf
MFKilla
New Member
Bro i have it. But im trying to do this
This app use PIDs throught Tourque Pro)
I use it already on my accord 2.0 turbo stage 3 (400+hp) Where I look all sensors online during a race ( Boost, AFR, MAF, Ignition, Intercooler temp and Knock Control) Now I wanna see Capacity level)
MrFixit
Well-Known Member
The PID has not changed, but...
I have to look back a few years to remember specifics, but I believe there was a basic problem with Torque Pro related to the buffer size that they used. I think the message size used by the Clarity overflowed the Torque Pro buffer, and that's why we ended up with Car Scanner. I think the buffer wrapped around when it overflowed and the data became scrambled.
MrFixit
Well-Known Member
Confirmed - Torque Pro does NOT work with the Clarity...
Here is the post from earlier in this same thread:
https://www.insideevsforum.com/comm...ry-capacity-readout.10531/page-19#post-178341
MFKilla
New Member
Do you have any contact with Car Scanner devs? May be Car Scanner team could do someting like this apk https://github.com/agronick/aa-torque/releases
MrFixit
Well-Known Member
We did have contact with them, and originally provided them with the PID's for the Clarity. It has been several years since then however.
A better approach would be to get Torque Pro to increase their buffer size. When we tried to work with them, they were unresponsive.
MFKilla
New Member
Sorry guys for my English) Its not my native language)
You’ve actually had 46.66Ah for the past 5.5 months.
MFKilla
New Member
Last charge show me 46.70. Its very interesting))
What is interesting about a difference of 4/100ths of an Ah between 2 measurements?