Charging and life recommendations...

[blentre]

Anyone have these? Is it best to do shallow discharges and not charge to 100% every night? I've read some other vehicles let you reduce maximum charge to something like 80% but I don't think this is available on the FFE. This may not be as big of a deal to life expectancy like always deep discharging. After my two way commute I was at 60% and debated plugging it in or trying to get a second day which should leave me around 20% before charging. I was a little concerned hearing about folks running their batteries down to a dead stop to test capacity and doing so frequently. I've always been of the mindset to avoid deep discharges and charge more often between uses. The smaller the depth of discharge the longer the battery will last. Perhaps I'm worrying about not and the Ford engineers have outsmarted me...

Thanks,

Brian

 

[JimB_FFE]

I asked someone at Ford about the lack of an 80% charge option and he told me that it's not necessary with the Focus.

I would not recommend compulsively topping off. Just charge whenever it works best for your schedule. Ford had a very sophisticated battery management system.

I usually charge when I get down to about 40 miles.

 

[davideos]

I did a little math the other day and I believe that the focus only charges to 80%. When you turn your car off, there are some statistics on the display left of the speedometer. It shows you what your average Wh/mile. Your batter is 23KWh. Now keep in mind what your range is just after you charge your car. If you divide 23000 by your average Wh/mile, you will end up with something more than what your car tells you is your range. However, Multiply 23000 by .8 and then divide by your average Wh/mile, and you will be very close to what your car reports is your range after a charge.

 

[blentre]

I believe it charges to 100% but tries to limit you to only drawing down 80% each cycle. As with any battery it's best to limit your depth of discharge and going to 0% is bad (drastically reduced cycles before dead). We should be using the top 80% of the battery and not charging to 80% of capacity. The shallower your discharge is within reason (10-50%) the longer it will last. This is the reason I have not done a full range test (drive her until she dies) on my FFE and would not recommend it.

I've had the same experience with my Polaris Electric UTV using flooded cells. The fuel gauge only shows the top 80% so that when it reads empty batteries still are actually at 20%.


http://www.altenergymag.com/emagazine/2012/04/a-comparison-of-lead-acid-to-lithium-ion-in-stationary-storage-applications/1884

"All lithium-ion cells are “deep cycle” meaning that they have the ability to be fully charged and discharged. The life of the battery will significantly increase if the depth of each discharge is limited to 80% of the rated capacity.

2,000 @ 100% DoD
3,000 @ 80% DoD"

 

[mountaineer]

I believe Brian has it right—the Ford engineers have outsmarted all us drivers. The charge/discharge limits needed to achieve very long battery life, and many other controls related to charge/discharge rate as a function of temperature and battery condition, are already built into the car's software. It's all done automagically behind the curtain, and you don't need to worry about it. Just use and charge the car as it says in the manual. Your traction battery's useful operating range will be, as I recall from other literature and fora, around 85% of the nominal 23 kWh, or about 19 kWh, though those numbers are a bit fuzzy and may depend on circumstances.