Battery indicator in Hybrid Mode

[TX NRG]

"The 2013 Ford C-Max and C-Max Energi are examples of what it takes to develop conventional hybrid and plug-in versions of the same vehicle—that is, many specific parts, software, and validation. Both cars have lithium-ion (nickel-manganese-cobalt oxide) cells, which are chemically very similar. But those in the plug-in C-Max Energi, which has a 21-mi (34-km) EV range, have thicker electrodes and store more energy. ....

 

The “full” or conventional HEV version of the C-Max has 76 of the power cells wired in series, rated at 1.4 kWh. The plug-in Energi has 84 of the energy type in series, rated at 7.6 kWh. The plug-in uses 6.5 kWh for EV range and allows a residual of 1.1 kWh for HEV operation.

 

The physical size of the Energi PHEV pack, of course, is much greater. The HEV cells are each 120 x 85 x 13 mm (4.72 x 3.35 x 0.51 in); the Energi's are 148 x 91 x 26 mm (5.83 x 3.58 x 1.02 in). And the Energi pack has higher peak voltage (361 vs. 327, during regenerative braking). There's comparable HEV capacity for such operations as idle stop/restart, Ford engineers said."

 

http://articles.sae.org/11705/

[jetjam]

Steve...who said that? Liion battery range is from 20% to 100%. For long life don't drain below 20% and don't leave fully charged at 100% for more than several hours. For storage charge to 60% and keep cool.

 

-=^Raja.

So if I'm leaving for a few weeks, leaving my car plugged in will damage the battery?  

[Russael]

A few weeks won't hurt it at all.  I believe "Long Term Storage" means a month or longer.  In that case, you'd want to drain enough of the battery's charge to get it around 60%.

 

You'll likely come back to a dead 12v battery though... that doesn't seem to keep a charge for very long.  I've let my car sit a week unplugged and didn't have any issues, but others have had varying degrees of discharge. 

[rbort]

I'd recommend that you don't leave it plugged in the whole time you're gone.  Leave it around 60% charge on the HVB and unplug everything from the sockets in the car, 12v or USB so that there is no additional drain on the 12v battery.  If for some reason it does die, then when you get home you just jump the battery and while jumped you can connect the HVB charger to initiate the charge from 60% back to 100 and it will charge the 12v battery as well in the process so you can disconnect the jumper cables once charging has started.

 

-=>Raja.

[stevedebi]

Steve...who said that? Liion battery range is from 20% to 100%. For long life don't drain below 20% and don't leave fully charged at 100% for more than several hours. For storage charge to 60% and keep cool.

 

-=^Raja.

I believe it was larry. The conventional C-Max is 1.5KW hours, with 1.1KW usable, but the SOC range in pure hybrid mode is measured at 33% to 66%, which equates to .5 KWh. I'm assuming that in maintaing mode (highway), the Energi and normal hybrids work the same, and have the same available energy.

 

If you think about it, it makes sense for them to work the same. A "normal" hybrid has already been maximized to use the battery efficiently at highway speeds, and Ford can just re-use the code from the hybrid in the Energi version.

Edited November 12, 2014 at 06:37 PM by stevedebi

[jetjam]

I'd recommend that you don't leave it plugged in the whole time you're gone.  Leave it around 60% charge on the HVB and unplug everything from the sockets in the car, 12v or USB so that there is no additional drain on the 12v battery.  If for some reason it does die, then when you get home you just jump the battery and while jumped you can connect the HVB charger to initiate the charge from 60% back to 100 and it will charge the 12v battery as well in the process so you can disconnect the jumper cables once charging has started.

 

-=>Raja.

I'm going to be gone for about 5 weeks.  Couldn't I leave it at 60% and put a 1amp battery tender auto charger on the 12 v battery?  Or would that gradually charge the HVB as well?? 

[rbort]

If you like you can do that, the 12v battery and the hybrid battery are not connected while the car is off.

 

-=>Raja.

[larryh]

I believe it was larry.

 

I believe he was referring to

 

Larry, OK I get the high SOC - 80% is what most LiIon batteries use for the "longevity", but they don't usually go below 40% on the low side. That Ford would allow in the 20's is surprising.

 

The range of energy stored in the Energi HVB varies from 1.0 kWh to 7.2 kWh.  The capacity is 7.6 kWh.  So that makes the actual range from 13% to 95%.  For the Hybrid HVB, the range is approximately from 0.5 kWh to 1.0 kWh, assuming the capacity 1.4 kWh and the approximate range of SOC is 33% to 66%. 

Edited November 13, 2014 at 10:10 AM by larryh

[stevedebi]

I believe he was referring to

 

 

The range of energy stored in the Energi HVB varies from 1.0 kWh to 7.2 kWh.  The capacity is 7.6 kWh.  So that makes the actual range from 13% to 95%.  For the Hybrid HVB, the range is approximately from 0.5 kWh to 1.0 kWh, assuming the capacity 1.4 kWh and the approximate range of SOC is 33% to 66%. 

Larry,

Thanks for putting it all in one place.  Here is how I understand the system to work.

 

At highway speeds under normal circumstances, the Energi operates like the hybrid, correct? Therefore it has only .5 to work with (except when going downhill, where it can refill the main portion of the HVB instead of having the SOC max out like the conventional hybrid - but it takes a very good downhill).

 

The point is that at highway speeds the two vehicles basically act the same (maintaining mode); Ford does not make use of the extra capacity of the Energi.

 

EDIT: And I'm still surprised at the figures for the Energi. I would have thought it operated at the same 33% to 66% of the larger battery - for longevity.

Edited November 13, 2014 at 06:44 PM by stevedebi

[Hybridbear]

I believe he was referring to

 

 

The range of energy stored in the Energi HVB varies from 1.0 kWh to 7.2 kWh.  The capacity is 7.6 kWh.  So that makes the actual range from 13% to 95%.  For the Hybrid HVB, the range is approximately from 0.5 kWh to 1.0 kWh, assuming the capacity 1.4 kWh and the approximate range of SOC is 33% to 66%. 

The Volt uses a much narrower range, similar to the FFH & C-Max Hybrid.

 

For reference: the Focus Electric has a 23 kWh battery and uses 18.5-19.4 kWh. The exact number isn't known since it doesn't support Torque Pro and thus the only numbers come from a select few owners who received a prototype ScanGauge from LinearLogic. It appears that it charges up to a max ETE of 21.5 kWh and a minimum ETE of 2.0-2.5 kWh.

[stevedebi]

The Volt uses a much narrower range, similar to the FFH & C-Max Hybrid.

 

For reference: the Focus Electric has a 23 kWh battery and uses 18.5-19.4 kWh. The exact number isn't known since it doesn't support Torque Pro and thus the only numbers come from a select few owners who received a prototype ScanGauge from LinearLogic. It appears that it charges up to a max ETE of 21.5 kWh and a minimum ETE of 2.0-2.5 kWh.

Well, Ford is providing the required warranty, and the more battery, the better the MPG. But still surprising.

[openair]

The point is that at highway speeds the two vehicles basically act the same (maintaining mode); Ford does not make use of the extra capacity of the Energi.

 

EDIT: And I'm still surprised at the figures for the Energi. I would have thought it operated at the same 33% to 66% of the larger battery - for longevity.

If you replace "highway" with EV later this is mostly correct. Ford does make use of the extra capacity of the energi at highway speeds, in auto or ev now.

 

You'd probably be less surprised if you understood more about the chemical reaction that fuels the inner workings of these batteries. Ppl are often surprised when they try to take a little information and run with it. "A little knowledge is a dangerous thing." This thread is full of examples of that.

Edited November 13, 2014 at 10:41 PM by openair

[stevedebi]

If you replace "highway" with EV later this is mostly correct. Ford does make use of the extra capacity of the energi at highway speeds, in auto or ev now.

 

You'd probably be less surprised if you understood more about the chemical reaction that fuels the inner workings of these batteries. Ppl are often surprised when they try to take a little information and run with it. "A little knowledge is a dangerous thing." This thread is full of examples of that.

I think I understand the basic chemistry. But more importantly, I've driven a Ford hybrid for 6 years, and studied other manufacturers hybrid implementations. Based on these, I still find it surprising that they allow the battery to go as low as larry indicates. I've not seen anyone allow that large of a range, and the conventional hybrid doesn't allow it either.

 

EDIT: And yes, I did mean EV Later by "Highway". Auto would apply only if the main HVB is depleted, which is where the driver will always end up if they attempt a highway drive at EV Now for any length of time. This thread is about hybrid mode, so I thought that was pretty clear.

 

As to "a little knowledge", I concur with that statement - and you never know who is going to exhibit that behavior next!

Edited November 13, 2014 at 11:19 PM by stevedebi

[openair]

Personally, having driven a hybrid for any number of years is less, not more, important than understanding the physics behind the batteries if you want to make judgements about how the battery is designed.  Especially since before 2013, "ford" hybrids used an entirely different battery.

 

They may end up there, but to end up there, "ford" would have had to have made use of the "extra capacity of the energi" and there is no longer any extra left to draw from.  It does make use of this capacity, once depleted, if it has need.  Such as long period of regen going down a hill.  Which you said in your post.  The only logical conclusion left to draw is that the extra capacity you refer to (since you just said it does use that capacity in some form) is charge in the HVB.

 

"At highway speeds under normal circumstances, the Energi operates like the hybrid, correct?"  Always driving down the highway with your HVB depleted may be normal for you but it's not for me and defeats the purpose of having an ev later mode.  But yes, since "this thread is about hybrid mode," it is pretty clear that when "at highway speed" in ev later or hybrid mode, "the energi operates like the hybrid."

Edited November 14, 2014 at 03:47 AM by openair

[stevedebi]

Personally, having driven a hybrid for any number of years is less, not more, important than understanding the physics behind the batteries if you want to make judgements about how the battery is designed.  Especially since before 2013, "ford" hybrids used an entirely different battery.

 

They may end up there, but to end up there, "ford" would have had to have made use of the "extra capacity of the energi" and there is no longer any extra left to draw from.  It does make use of this capacity, once depleted, if it has need.  Such as long period of regen going down a hill.  Which you said in your post.  The only logical conclusion left to draw is that the extra capacity you refer to (since you just said it does use that capacity in some form) is charge in the HVB.

 

"At highway speeds under normal circumstances, the Energi operates like the hybrid, correct?"  Always driving down the highway with your HVB depleted may be normal for you but it's not for me and defeats the purpose of having an ev later mode.  But yes, since "this thread is about hybrid mode," it is pretty clear that when "at highway speed" in ev later or hybrid mode, "the energi operates like the hybrid."

Yes, I was very interested in the switch from NiMH to LiIon, which is why I researched before I bought, especially on longevity. I stand by my statements as to what larry has reported on the battery percentage range. I'm not doubting larry's numbers (that would never be wise) - just trying to get more information. If you have contrasting information that indicates that such a wide range is used elsewhere, or presents no issue, I'd love to read it and learn more. Please provide the URL, or upload documentation. 

 

As an Energi driver, for most folks the vehicle will be in EV Later on the highway, which means it operates like the conventional model hybrid. That means that we can learn from the conventional hybrid drivers when they discuss techniques.

 

I am working on techniques for when to switch back to Auto on the highway, either to provide extra boost or to gather excess energy. It is quite possible to recharge the HVB from highway driving - the trick is to do so without burning excess gas. I don't do much highway driving, so it is going to be a long process to get results. On my first attempt I got about 4 MPG more over the same driving cycle than just leaving it in EV Later. Once I establish what works, I plan to share my experience.

 

If you prefer to just leave it in EV Later, no big deal. I like to explore possibilities.