Use Lightning like a Power Wall? Peak load shaving, not backup?

[Sklith]

BMW i3 and Chevy Bolt.
I spoke with quite a few highly trained i3 techs (even German) and all of them said no reserve trying to fix an issue.
Every Bolt technical manual says no also.

Here's a pretty nerdy article on the Bolt's battery buffers.
https://allev.info/2019/02/bolt-battery-buffer/

In summary, it has no buffer. Full is full, and 0% is completely dead.

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[Kiggulak]

Tell me what the vehicles were and I might be able to tell you if they actually had a hidden reserve. the vehicle might say 100%, but the cell capacity and the xSxP configuration might say something different.

What about the 2013 Ford Focus Electric? Any hidden reserves or recommendations like you gave for the Bolt?

 

[Solar_EE]

It will impact the lifespan of the truck battery. There are finite full charge cycles in a Li-ion battery (500?). You'll be adding 365 discharge/charges a year if you are powering the house at night with the truck.

Probably cheaper and more cost effective to buy some old cheap batteries for house backup.

The original post talked about minor charge/discharge cycles of less than 10% of the battery. That does not wear out the battery like 100% cycling. If you compare the cost of the Ford 100 kWh battery in the Ford Pro model ($40K) it is the equivalent of more than 7 Tesla 13.5 kWh powerwalls. So really for this application you are getting a much bigger battery for less money- with a free truck also! Tesla powerwall costs $10,000 each for 13.5 kWh or $70k if you bought 7.

 

[Solar_EE]

As someone that constantly runs a number of duty cycles on many different Li-ion cells for my day job, I can assure you that 10 10% cyles do not equal a 100% cycle. I can tell you that depth of discharge, delta SOC (State of Charge), charge/discharge currents, and temperature of cells all have a factor in cell life. For ideal conditions, cycle around 50% SOC, at the lowest possible current to meet needs, keep it to around a 20% delta, and keep cell temperatures around 25C.

Lifetime cycles for a specific type of cell are generally stated in 100% delta in SOC (Vmax to Vmin) and at maximum manufacturer recommend current levels (both charge and discharge).

For a cell I am testing now, that is in a current OEM vehicle, the temperature is the dominant factor in the decrease in capacity based on the calendar life tests. It is very dramatic at 55C, hence the OEM works very hard to keep the temperatures at 25C.

But yes, all charge/discharge cycles will degrade the battery to some degree.

Thanks for providing some real data on this. In my application my garage stays between 7C and 29C year round so a slight discharge of the 100 kWh battery will not heat it up much. Using the Lightning battery during peak grid times could really help the overall grid. I think this is something Ford will work on as these trucks roll out by the hundreds or thousands.

 

[Lightning_Bob]

I'm curious, and we may not know yet, but is it possible to use the Lightning like a battery bank in conjunction with solar? I would like to have the Lightning power our house every evening to avoid high electric prices, then charge back up from the grid at night. I know the charging part of that is regular functionality, but what about powering the home when the grid is still active? Not talking about power-out backup here, but more peak-load shaving.

I was looking into a Tesla Powerwall, but the cost is too high. And if I recall it was something like 15kWh storage. I have concerns about extra wear on the Lightnings battery, but really it's only 10-15% discharge in comparison, and I likely wouldn't need the whole 15kWh every day either, maybe a 1/3 of that, so really not talking about much load on the truck. Might be a nice way to make a few bucks back every year.

How would the wiring have to look in conjunction with solar for this? How would the truck know how much to discharge in conjunction with solar? How does it know the difference between powering the home and discharging to the grid? Just daydreaming here. Thanks for any thoughts.

I was thinking the easiest way to do this without home integration (that may make things complicated) with the assumption your house does not need more than 7.2kw at 220v and 2.4kw at 120v:
- Get the Pro Power Onboard upgrade so you have 7.2kw 220v and 2.4kw 120v
- Set the truck or your EVSE to only charge at night
- Plug the 220v and two of the 120v into an (smart?)automatic transfer switch/hybrid inverter(s)
- Set your hybrid inverter/transfer switch to switch your house to grid at night, and to your truck during the day

- Downside is that you'll need to unplug/plug 4 wires (J1772, 1x 220v, 2x 120v) from your truck if you want to use it

- If your house will not need more than 7.2kw - the setup will be simpler since you will not need to add on additional transfer switches and segregate your circuits for the 120v, or plug in the 2x 120v circuits from the pro power onboard...

... If you compare the cost of the Ford 100 kWh battery in the Ford Pro model ($40K) it is the equivalent of more than 7 Tesla 13.5 kWh powerwalls. So really for this application you are getting a much bigger battery for less money- with a free truck also! Tesla powerwall costs $10,000 each for 13.5 kWh or $70k if you bought 7.

This was my initial thought as well - If you needed 100kw battery you are basically getting a free truck to go with it....then realized, with the HIS - it can only output 9.6kw. if you've got multiple powerwalls or power banks one could configure the output to be much greater than 9.6kw - some houses may how power surges greater than 9.6kw (ie multiple things starting at the same time - AC compressor, well pump, sump pump, etc)...which kinda led to my other question on this sub forum if one could use the On Board Power Pro (7.2kw 220) and the HIS (9.6kw 220) simultaneously (on different circuits/transfer switches)... If so this may be enough to address the limited amount of power output...

 

[RidetheLightning]

The original post talked about minor charge/discharge cycles of less than 10% of the battery. That does not wear out the battery like 100% cycling. If you compare the cost of the Ford 100 kWh battery in the Ford Pro model ($40K) it is the equivalent of more than 7 Tesla 13.5 kWh powerwalls. So really for this application you are getting a much bigger battery for less money- with a free truck also! Tesla powerwall costs $10,000 each for 13.5 kWh or $70k if you bought 7.

I thought the same at first, but Tesla does discounts with multiple battery purchases in a system though. I can't find a price list without requesting a quote from Tesla on their website, but this site reports the cost and I've seen it mentioned a few other places that there are volume discounts if you buy a multi-Powerwall system. It would really be about $56.5k for 7 powerwalls installed and you'd be at 4.5 less kWh with the Tesla system. Compared to a Pro, you'd still get a free truck though and a lot of money left over to get the FCSP and Home Integration unit installed. Tesla has the easy load shifting for time of use already set up for you though. https://climatebiz.com/tesla-powerwall-cost/

 

[Maquis]

I see no reason why the F150 Lightning cant be used as a battery backup. We need a SAE J1772 pigtail that has a communication box that tells the F150 to send DC voltage when commanded. This would need to feed to a DC to AC inverter, then a breaker box with a disconnect to act as the input to the house breaker box.

Is it that Ford just has not told us if this is possible to tell the truck to send power back through that port?

The biggest reason is that cycling the battery reduces its life. As a stationary battery degrades, you’d likely not notice until it got really bad. You’ll definitely notice when your truck’s range is reduced 20%. Or more.
For occasional backup power, it makes sense. Trying to use it for peak shaving when connected to the grid every day doesn’t.

Ford likely won’t support peak-shaving simply due to risk to the battery warranty.

 

[merek]

The biggest reason is that cycling the battery reduces its life. As a stationary battery degrades, you’d likely not notice until it got really bad. You’ll definitely notice when your truck’s range is reduced 20%. Or more.
For occasional backup power, it makes sense. Trying to use it for peak shaving when connected to the grid every day doesn’t.

Ford likely won’t support peak-shaving simply due to risk to the battery warranty.

Pretty sure Ford advertised that feature explicitly, but said it would be enabled via a later software update.

I see no reason why the F150 Lightning cant be used as a battery backup. We need a SAE J1772 pigtail that has a communication box that tells the F150 to send DC voltage when commanded. This would need to feed to a DC to AC inverter, then a breaker box with a disconnect to act as the input to the house breaker box.

Is it that Ford just has not told us if this is possible to tell the truck to send power back through that port?

You are describing literally the Home Integration System.

 

[Maquis]

Pretty sure Ford advertised that feature explicitly, but said it would be enabled via a later software update.

Maybe so, I don’t recall seeing it.

 

[jk340]

Thanks to the OP for asking this question. I have solar and 2 Powerwalls and was wondering about this. The solar + Powerwalls saves us quite a bit on power every day from Spring through Fall and kept us going through far too many power outages. I do have an order for an F-150 Lightning so was curious about what I could add with the F-150 and the correct hardware. Based on the discussion here it does not seem that the F-150 backup route is worth pursuing.

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