Interesting: "Value" charging uses more electricty

http://velobusdriver.com/2014/12/28/c-max-energi-value-charge-uses-more-electricity/

Sounds like the author's battery/battery management system has a problem. The normal vampire draw for the Focus is about 2.5 watts, not 70 watts. If the temperature is too hot or cold the TMS will cycle, but his graph doesn't show cycling; and you wouldn't want to avoid TMS conditioning by leaving it unplugged anyway.

GladeStorm said:

Sounds like the author's battery/battery management system has a problem. The normal vampire draw for the Focus is about 2.5 watts, not 70 watts. If the temperature is too hot or cold the TMS will cycle, but his graph doesn't show cycling; and you wouldn't want to avoid TMS conditioning by leaving it unplugged anyway.

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It does seem really high. Perhaps his Energi was charging the 12V battery during this test. It may also have been running the battery fan. The Energi doesn't have liquid TMS, just a fan. It will run as soon as the car is plugged in if the battery is warm.

When the Energi battery is cold the car will trickle charge it as soon as it is plugged in to work on warming up the battery before doing the quick charge during the value charge window.

Since he posted this data in December it's possible that the battery was either hot or cold. The Energi will let the battery get hotter in the summer when ambient temps are warmer, sometimes waiting until the battery reaches 80+ F before turning on the fan. In the winter the Energi will turn on the fans much sooner to try to keep the battery between 50F & 70F. If the battery is below 50F the fan will come on to warm it with cabin air, if the temp is above about 70F the fan comes on to cool the battery. I've seen times where the fan came on once the HVB reached 70F and cooled it all the way down to 55-60F before turning off. When the Energi is in "hybrid" mode the HVB doesn't really heat up. So if you start out in EV Now and warm up the HVB enough for the fan to come on it will cool the battery down significantly while you're in EV Later before turning off the fan.

From what I've observed with our Energi it will charge the 12V battery regardless of $$$$ windows and it will run the battery fan regardless of $$$$ windows.

One Energi owner that I'm friends with has TOU rates for his house and because of how his Energi would draw so much power immediately after plugging it in he has a timer on his EVSE so that the EVSE is not powered until his TOU rates start. Then the Energi isn't set to begin charging until later in the night. This allows the EVSE to boot up without having a fault because the car is plugged in already.

hybridbear said:

When the Energi battery is cold the car will trickle charge it as soon as it is plugged in to work on warming up the battery before doing the quick charge during the value charge window.

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The FFE will also trickle charge the battery when temps are very cold (below freezing).

jmueller065 said:

hybridbear said:

When the Energi battery is cold the car will trickle charge it as soon as it is plugged in to work on warming up the battery before doing the quick charge during the value charge window.

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The FFE will also trickle charge the battery when temps are very cold (below freezing).

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Yes, but that is a short process. As I've reported on elsewhere, we commonly see the FFE charge immediately during winter upon being plugged in at home for somewhere from 3-15 minutes depending on how cold the battery is. The Energi owner's chart shows a consistent power draw for many hours. This is not at all consistent with the behavior of the FFE when connected to a 240V EVSE.

hybridbear said:

Yes, but that is a short process. As I've reported on elsewhere, we commonly see the FFE charge immediately during winter upon being plugged in at home for somewhere from 3-15 minutes depending on how cold the battery is. The Energi owner's chart shows a consistent power draw for many hours. This is not at all consistent with the behavior of the FFE when connected to a 240V EVSE.

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I've seen mine charge for a good hour or more, not just 15 minutes--depending on temperature and if I have it parked outside or not.