OBDII data for HVB

[hybridbear]

Thanks to the FORScan Android app I've been able to start gathering data about the HVB. Here's some data I've gathered so far:
From the BECM
Pack volts ~351 @ 92% SOC
Min volts 4.08
Variance 0.01 V
HVB temp 79
Max 81, Min 77

Pack volts ~347-348 @ 84% SOC
Min volts 4.04
Variance 0.01 V
HVB temp 68
Max 72, Min 66

Pack volts ~336-337 @ 62% SOC
Min volts 3.91
Variance 0.01 V
HVB temp 72
Max 75, Min 70

Pack volts ~298 @ 9% SOC
Min volts 3.44
Variance 0.07 V
HVB temp 82
Max 86, Min 79

Note: The SOC in these measurements is Absolute, not displayed. It seems that the range of battery that we use is ~7-8% to 92% SOC according to that PID.

When discharging the voltage decreases & variance increases. When charging the voltage increases & variance increases. Lower SOC means lower voltage & more variance.

Peak discharge amps is around 340 at ~320 V. That's what I saw when flooring it to go from 30-60 MPH. The variance got up to 0.07 volts. Under normal acceleration it goes up from 0.01 up to about 0.03. At low SOC the variance was mostly 0.05 to 0.07 even when at rest.

 

[hybridbear]

Cell variance seems to go up from 0.01 volts to 0.02 volts once the current draw exceeds 50 amps. Once it exceeds 100 amps the variance goes up from 0.02 to 0.03 volts. This is true of both charging & discharging the HVB.

The maximum discharge limit is 110 kW and the maximum charge limit is 60 kW. A 60 kW charge rate would equate to 175+ amps depending on the voltage of the pack at that point.

 

[hybridbear]

Today I drove a 41 mile one-way commute in the Focus. MFM & the Trip Summary shows 8.6 kWh used. The starting ETE minus the ETE when I arrived at my destination shows 9724 Wh used. Something doesn't add up...

 

[jmueller065]

Really, looks legit to me:
9724/1024 = 8.6 right? j/k

(My OBDII Mx is arriving tonight..)

 

[sefs]

Today I drove a 41 mile one-way commute in the Focus. MFM & the Trip Summary shows 8.6 kWh used. The starting ETE minus the ETE when I arrived at my destination shows 9724 Wh used. Something doesn't add up...

ETE will change based on a bunch of things. It's a calculated value. If you're in a cold garage, and go out to a hot sunny day and just sit there, you can see the ETE tick up and up and up. What you used as reported by the car's trip meter is based on current * voltage * dt summed together for your trip.

 

[hybridbear]

Today I drove a 41 mile one-way commute in the Focus. MFM & the Trip Summary shows 8.6 kWh used. The starting ETE minus the ETE when I arrived at my destination shows 9724 Wh used. Something doesn't add up...

ETE will change based on a bunch of things. It's a calculated value. If you're in a cold garage, and go out to a hot sunny day and just sit there, you can see the ETE tick up and up and up. What you used as reported by the car's trip meter is based on current * voltage * dt summed together for your trip.

That's true. In fact, after I arrived at work I sat in the car for a few minutes checking other PIDs in FORScan and I was able to watch the ETE rising while parked.

It was also interesting to note that the HVB temp dropped as I drove 40 miles and used almost 9 kWh from the pack. It was 90 F when leaving home and 86 F when I arrived at work. The HVB cooling system was not active. The outside temp was about 65 F. I'll be curious to see what the temp is after the car sits out in the sun all day with a predicted high temp of 85 F.

 

[jmueller065]

Well now I'm in the OBD-II Forscan club LOL.

For my first drive/commute recording data: Max battery current = 322A, min current (regen) = -161. From Hybridbear's notes these look to be close to the FFE's limits (since I knew I was recording I floored it from a dead stop a couple of times to get the max).

Forscan's formula for vehicle speed (or the battery control module's reception of vehicle speed) seems to be off a bit.

In addition the beta's metric/imperial setting doesn't seem to work.

 

[hybridbear]

Coming home the trip summary showed 7.8 kWh used but the ETE only decreased by 7580 Wh...

 

[WattsUp]

Coming home the trip summary showed 7.8 kWh used but the ETE only decreased by 7580 Wh...

Your screenshot shows a read-out named "BAT_TO_EMPTY" labeled "Watt".

Shouldn't that be "Watt-hours" or some other unit of energy?

 

[hybridbear]

Coming home the trip summary showed 7.8 kWh used but the ETE only decreased by 7580 Wh...

Your screenshot shows a read-out named "BAT_TO_EMPTY" labeled "Watt".

Shouldn't that be "Watt-hours" or some other unit of energy?

That is correct. Other users have reported this error to FORScan.

 

[hybridbear]

The ETE is not reflective of the SOC of the HVB but rather of how much energy is available before your get the charge depleted SSN.

We've typically seen a "full" charge show around 19.1-19.7 kWh as the ETE. The couple times we've been down close to 0% & 0 miles remaining the ETE has shown only a few hundred Wh. Yesterday the ETE showed 440 Wh when we got home and the car was predicting 4 miles of range remaining. It appears that the range estimate isn't strictly based on ETE & your recent Wh/mi consumption, but rather based on the Displayed SOC %. This would explain why I've felt the last 5 miles of range drop much faster than expected when you get near 0 miles. Based on an ETE of 440 Wh the car should show 2 miles of range remaining. One of these days I want to take the car all the way down to the charge depleted SSN to see what the ETE shows at that point and what happens when you keep driving past the charge depleted SSN. If it shows the charge depleted SSN before the ETE hits 0 then that range prediction was really off.

 

[michael]

I've yet to understand how this works. When fully charged, my ETE varies, generally 18.5 give or take. But once I start driving, it drops much faster than the trip consumption would indicate. After a few miles, the drop in ETE matches the consumption, more-or-less.

When I did a heater-full-blast test, it only showed about 17.5 kWh til SSN.

 

[hybridbear]

I've yet to understand how this works. When fully charged, my ETE varies, generally 18.5 give or take. But once I start driving, it drops much faster than the trip consumption would indicate. After a few miles, the drop in ETE matches the consumption, more-or-less.

When I did a heater-full-blast test, it only showed about 17.5 kWh til SSN.

It's possible that you have lost more capacity than we have. You have at least 3x as many miles as we do. Our car has less than 12,000 miles on it.

 

[hybridbear]

Last night I had to go somewhere unexpectedly that was beyond the EV range of the Energi so I stopped by my wife's office to pick up the Focus. It had been sitting in the sun all day. Ambient temp was around 70 degrees. The HVB temp when I started the car was 81 F. The car immediately began cooling the HVB. The TMS ran until the HVB temp dropped to 79 F. This took less than 5 minutes. Shortly before I reached my destination (about 15 miles away) the HVB temp rose back to 81 F. The TMS did not activate again. After the car was parked in the shade for a few hours the HVB temp was back down to 79 F for the trip home and it stayed their the entire way home (about 20 miles). The TMS did not activate during the trip home. This morning the HVB temp was down to 75 F as the Focus sat unplugged overnight because the Energi needed to be charged.

The hottest HVB temp I've seen so far was 85 F which was shortly after charging. Charging seems to raise the HVB temp by at least 5 degrees on our car. Our car is parked underground at our apartment and the garage temp is usually around 70-75 degrees in the summer.

It appears that while the TMS will definitely engage above 98 F as others have noted, it may also engage in other circumstances, particularly when the car has been parked in the sun for hours.

 

[michael]

I have never ever seen that happen. I wonder if there is a software upgrade that does more aggressive cooling that mine does.

 

[michael]

Today, for example, when I started out the ETE showed 18.5 kWh.

By the time my consumption showed 4 kWh, the ETE had dropped to 13.2. So the ETE dropped by 5.3 while the consumption was only 4. This is a typical pattern, I see it all the time. Battery temp mid 80's, not cold.

 

[hybridbear]

Our full charge ETE has ranged from a low of 19,006 Wh to a high of 19,936 Wh in the dozen or so data points I've collected so far. The Abs SOC has ranged from 89.41 to 91.88 at a full charge. It appears that the ETE will hit 0 around the time you get the charge depleted SSN. This means our car predicts that it can use about 19.5 of the 23 kWh for driving range.

 

[michael]

Mine has never been that high, interesting...

 

[hybridbear]

Mine has never been that high, interesting...

How many miles were on your car when you started tracking?

 

[michael]

Don't really know....call it maybe 20K??????