Hybrid Battery Temperature Monitoring

[ZeroDay]

@ZeroDay - if you can get some early coasting in - the system seems more willing to charge when cold, which starts warming it up, and quicker to the point it's more willing to discharge.
Then again - I was only near 0 or tad below F.
Highway speeds don't seem to add much in the way of charging anyway - which may have been good at -40!

I never have issues -39 and above! My commute is generally flat and slow enough it'll dump the entire battery and charger itself back up with the engine multiple times. I go full electric at full road speed quite often.

Sponsored

 

[MakinDoForNow]

I'm assuming the system is more of a battery heater than a battery cooler. Last winter I had one day below -40 and it would NOT use the electric motors or go into electric mode at all even after an hour of low speed highway. The truck was sluggish it felt like towing a heavy trailer and forgetting to use tow mode.

There is a heat recovery device in the exhaust near the muffler to heat battery coolant to help get HVB above 32°F so HVB can start being charged (lithium ion limit for longevity). Once battery is warm enough charge /discharge will warm it up to 60°F where sizes able amps can happen. The ice will be running generator and power for moving until HVB is warm enough to be used.

 

[Cherokee]

These seemingly normal battery operational temps are not any concern. No need to monitor at all.

 

[Darryl]

No lights, no performance degradation, no problem.

 

[Mavster Mechanic]

No lights, no performance degradation, no problem.

I mentioned elsewhere one time at above 120°F I had no regen with "L" but still had regen using the brake pedal.

Still odd to me I saw no effort to cool the battery. I just had to wait for it to come down below 120°F by not using it for a while.

 

[HeyBales]

I mentioned elsewhere one time at above 120°F I had no regen with "L" but still had regen using the brake pedal.

Still odd to me I saw no effort to cool the battery. I just had to wait for it to come down below 120°F by not using it for a while.

So even though in Low mode the system changes the Amp rate of Regen depending on the speed you are coasting down from, and constantly the whole time almost - the system isn't willing to back off the amount earlier on a hot HVB.

So did it almost feel like Neutral coasting down in Low mode then?

Curious if you were able to get the Brake regen right almost to the max during that time - didn't seem like it was backing off a bit, like only allowing a certain max Amps?

I guess like The Tricks for 12VB - just go for a change of action based on a switch setting and temp in this case. Even though you can equal the effect at the same temp just fine.

 

[Mavster Mechanic]

So even though in Low mode the system changes the Amp rate of Regen depending on the speed you are coasting down from, and constantly the whole time almost - the system isn't willing to back off the amount earlier on a hot HVB.

So did it almost feel like Neutral coasting down in Low mode then?

Curious if you were able to get the Brake regen right almost to the max during that time - didn't seem like it was backing off a bit, like only allowing a certain max Amps?

I guess like The Tricks for 12VB - just go for a change of action based on a switch setting and temp in this case. Even though you can equal the effect at the same temp just fine.

Coasting in "L" with a 120°+ HVB

INSTANT fuel cutoff and engine rev to ~4000 RPM.

Zero amps of regen even though battery was about 39% charged. But it was slowing from engine brake.

 

[Mavster Mechanic]

This Morning: Ambient 63°F

Still surprising to me battery is so warm on such a cool day. In more or less steady state (65 to 74 MPH) freeway driving. Some GENTLE rolling hills. Not many today.

Does yours behave the same??
Are you seeing similar numbers??

 

[MakinDoForNow]

Coasting in "L" with a 120°+ HVB

INSTANT fuel cutoff and engine rev to ~4000 RPM.

Zero amps of regen even though battery was about 39% charged. But it was slowing from engine brake.

120° is not a hot HVB. Li ion battery will charge/discharge efficiently the warmer it gets. University tests showed about 170° where heat phase change starts softening Chrystal structure. Most frequent recommendation is to reduce transfer activity at 148°F. Ford may not use coolant loop for cooling if ambient is not low enough to handle necessary BTU's
Then at 39%+SOC ice will be needed to brake for an indefinite time. Then when SOC drops to 20-22% or some other reason ice needs to run regen braking resumes until needed again. Pretty much HVB SOC from 40-70% appears to be reserved for regen brake pedal regen and switching of electrical needs. Only programmer may only know....
If ice reaches max rpm then you may see some hydraulics happening or may drop out of L I have no idea.

 

[inline_five]

Since the vast majority of OAT's are 100° and below you'd thing a separate radiator would make sense for the battery coolant.

A different source, similar numbers:

 

[MakinDoForNow]

Since the vast majority of OAT's are 100° and below you'd thing a separate radiator would make sense for the battery coolant.

A different source, similar numbers:

The hybrid radiator is divided with the bottom 20% +/- being the portion used for HVB.

 

[HeyBales]

Hmmm - not seeing that high.
But notice in chart if my charging/discharging profile seems similar to yours.
Typical drive to work (I won't mention a little over 10 min and 5 miles) - downhill to highway, rolling hwy, then flattish to work.
I converted the amps to kW since there were some huge spikes ruining the scale.

Starting temp 82 in DCDC Conv & HVB, 86 F in cat & coolant.
After overnight - they really should be matching. Didn't have ambient temp sensor, hoping it adjusts accuracy based on those.

So even with some points of HVB max 32kW discharge on highway (turbo 43 HP!), or max 27kW charge on exit ramp - just doesn't get that high even with higher starting temp.
From what you've found with no real cooling - it would have eventually I suppose.
It was dropping when back at city driving and more charge/discharge switching, but max airflow thru engine bay too, despite less airflow over HVB undercarriage.

Data file shows grill shutters too - but not sure how much that would effect HV coolant circuit at the radiator, since 2 fins missing on top and bottom areas. If you didn't have AC on for your trip - perhaps it is effective.
0% open when no AC, which didn't last long starting at 83.
With AC on - 100% open sitting or low speed, down to 60% open when on highway.
So perhaps you were cool enough with outside air - shutters remained closed, which would explain your higher engine coolant temp I never reached.

 

[inline_five]

The hybrid radiator is divided with the bottom 20% +/- being the portion used for HVB.

Yeah, I was aware, just doesn't seem like it's doing the job, at least for @Mavster Mechanic

Hmmm - not seeing that high.

Those temps are more in line with what I would expect. Maybe there is a blocking for @Mavster Mechanic or something.

 

[HeyBales]

120° is not a hot HVB. Li ion battery will charge/discharge efficiently the warmer it gets. University tests showed about 170° where heat phase change starts softening Chrystal structure. Most frequent recommendation is to reduce transfer activity at 148°F. Ford may not use coolant loop for cooling if ambient is not low enough to handle necessary BTU's
Then at 39%+SOC ice will be needed to brake for an indefinite time. Then when SOC drops to 20-22% or some other reason ice needs to run regen braking resumes until needed again. Pretty much HVB SOC from 40-70% appears to be reserved for regen brake pedal regen and switching of electrical needs. Only programmer may only know....
If ice reaches max rpm then you may see some hydraulics happening or may drop out of L I have no idea.

I guess Ford considers the 120 F too hot. Perhaps even better for longevity.

They appear to have designed the simple idea that if Low is used, where max regen rate would occur automatically - don't allow the regen no matter the SOC% available to charge.

But, when regen braking at the same 120 F - go ahead and allow possibly the exact same rate of regen. Going into the pads causes the same max regen rate.

I do wonder though - is there a limit to that regen braking region, if for too long like a long downhill, or gets too hot from regen - does the system enable the same engine-braking and stop the charging, even though plenty of SOC% left to recharge?

 

[MakinDoForNow]

I guess Ford considers the 120 F too hot. Perhaps even better for longevity.

They appear to have designed the simple idea that if Low is used, where max regen rate would occur automatically - don't allow the regen no matter the SOC% available to charge.

But, when regen braking at the same 120 F - go ahead and allow possibly the exact same rate of regen. Going into the pads causes the same max regen rate.

I do wonder though - is there a limit to that regen braking region, if for too long like a long downhill, or gets too hot from regen - does the system enable the same engine-braking and stop the charging, even though plenty of SOC% left to recharge?

The temperature of the stator in the drive motor may get too hot or much more likely somewhere in the electronics. Driving stop and go in "L" up to 60 mph will activate engine braking in 3-4 miles on no more than a few +/- 15 feet elevation.
Someone has posted that he leaves home and has a long downhill (3-5?) miles and his regen stops before he gets to bottom.

Sponsored