# LEAFSPY PRO kW or Ah x volts?

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#### Jbechtold

##### Member
My current (and 5th) Leaf is a nearly new 2020 SL Plus. I love it!
My question is:
When I look at Leafspy Pro it reports XX kilowatts. But when I look at the data screen and multiply current Battery Volts times Amp Hours, I get a larger (and closer to what the car should have) number of kW by about 10%.
I know from years of experience with many Leafs that the dashes lie like crazy, so Leafspy is my best option. What can I believe?
Thank you for any input!
John

Keep in mind that that the battery loses voltage as it discharges. You start at 403VDC but end up about about 300VDC at full discharge. So it depends what voltage you use to calculate KWH. Your best bet is to go by the GIDS value in Leafspy. If your car is like mine, there's a lot of energy left when the battery gauge gets down to 10% Even at low battery warning I've got 100 GIDs left. That's about 30 miles of range. VLB warning is 50 GIDs by the way. Hope that helps.

Thank you for your thoughtful reply. I admit, I've not learned enough about GIDs. It's very difficult to find an explanation of how they are calculated (or even what GID stands for).

I'm aware of the voltage drop, but that happens as watt hours are removed from the battery. Are you saying that volts times Amp hours doesn't equal watt hours? I don't think the voltage dropping while discharging means the watt hours were never there. It's just part of the calculation that shows the current watt hours, and drops as they do.

I also know all about loss of capacity over time/miles. My previous four Leafs taught me a lot. All batteries are not created equal! My first 2018 still had 40+ kW after 18k miles and constant fast charging for LYFT driving. My last 2018 came with a bad module in the HV battery. After 3 visits to the dealer, I finally convinced then that "If it charges and drives, you're good, no warranty issue" is not an acceptable response to a car that dies on the freeway while showing 75 mile range left!
They said they replaced the module, but the capacity dropped to 80%, and that module's voltages are whacko, so I'm pretty sure they somehow just cut the system's access to that module.

But as I was shopping for a good used SL Plus, I found that Leafspy pro showed around 54 kW at 100% for all five cars that I checked, regardless of year model or mileage. I checked a 2019 (40k mi), 3 2020's (18k-38k mi) And a 2021 (13k mi), and none of them showed more than 54.5 kW at 100%. But they show 62-64.5kw when calculated from the volts and amps. Hence my question about what is accurate, And, did they ever really have 62kW, because all range and economy indications point to the 55 kW being accurate, and I'm starting to think that's all the Plus models ever had.

The term "Gid" refers to a unit of energy that was being reported by the BMS, and that was 'discovered' by the late Gary Giddings - it was named in his honor. I'm sure that Nissan has their own name for it, but they have never divulged it.

Jbechtold said:
Thank you for your thoughtful reply. I admit, I've not learned enough about GIDs. It's very difficult to find an explanation of how they are calculated (or even what GID stands for).

I'm aware of the voltage drop, but that happens as watt hours are removed from the battery. Are you saying that volts times Amp hours doesn't equal watt hours? I don't think the voltage dropping while discharging means the watt hours were never there. It's just part of the calculation that shows the current watt hours, and drops as they do.

I also know all about loss of capacity over time/miles. My previous four Leafs taught me a lot. All batteries are not created equal! My first 2018 still had 40+ kW after 18k miles and constant fast charging for LYFT driving. My last 2018 came with a bad module in the HV battery. After 3 visits to the dealer, I finally convinced then that "If it charges and drives, you're good, no warranty issue" is not an acceptable response to a car that dies on the freeway while showing 75 mile range left!
They said they replaced the module, but the capacity dropped to 80%, and that module's voltages are whacko, so I'm pretty sure they somehow just cut the system's access to that module.

But as I was shopping for a good used SL Plus, I found that Leafspy pro showed around 54 kW at 100% for all five cars that I checked, regardless of year model or mileage. I checked a 2019 (40k mi), 3 2020's (18k-38k mi) And a 2021 (13k mi), and none of them showed more than 54.5 kW at 100%. But they show 62-64.5kw when calculated from the volts and amps. Hence my question about what is accurate, And, did they ever really have 62kW, because all range and economy indications point to the 55 kW being accurate, and I'm starting to think that's all the Plus models ever had.
As far as I can tell, 1 GID equals 82.5w in my '22 SV+. In my 2016 SL it was about 74w. YMMV. The problem with V x AH is that the voltage drops as the battery discharges. 175AH x 403 VDC works out to 70 KWH clearly in excess of the battery's actual capacity. Nissan states that the nominal voltage is 360VDC. That would give you a 63 KWH battery when new. As the battery ages, you will see the AH reported in Leafspy drop. The number of GID's available at full charge will follow the AH reading. The number of GID's at full charge does bounce around a bit for me (+- 10 depending ). The AH reading is stable and declines slowly over time. I'm currently at 166.87 AH and 719 GID"S. Going by the AH reading for the battery's health and GID's for state of charge seems to be the best bet.

Just as a side note, the "guess-o-meter" in my '22 does seem more realistic in it's readings then my '16 did.

Extremely helpful. I looked up Gary Gid, and found some good posts, thanks to your replies!

So what I'm getting is that basically GID's are a more accurate measure of watts that will come OUT of your battery, than looking at how many watts are IN your battery?

Since the GID value varies, is there an indicator of efficiency in there somewhere?

My next search is for charging efficiency. My after market dual voltage charger seems inefficient, using 1,400w with 120v and 3,600 with 240v, but Leafspy says (about) 1,080w and 3,260w in, respectively. 300+ watts lost in the conversion seems excessive. Is it the Leaf's internal charger or my aftermarket charger eating that up? Are there more efficient chargers out there?

I should probably look for a different thread for that, huh?

Jbechtold said:
Extremely helpful. I looked up Gary Gid, and found some good posts, thanks to your replies!

So what I'm getting is that basically GID's are a more accurate measure of watts that will come OUT of your battery, than looking at how many watts are IN your battery?

Since the GID value varies, is there an indicator of efficiency in there somewhere?

My next search is for charging efficiency. My after market dual voltage charger seems inefficient, using 1,400w with 120v and 3,600 with 240v, but Leafspy says (about) 1,080w and 3,260w in, respectively. 300+ watts lost in the conversion seems excessive. Is it the Leaf's internal charger or my aftermarket charger eating that up? Are there more efficient chargers out there?

I should probably look for a different thread for that, huh?
GID's are the better gauge for remaining capacity to empty. AH is a better gauge for absolute capacity.

Efficiency is always going to be better at 240V than at 120V. For your 240V charging that's about 90% Looks like housekeeping and overhead are nearly the same for either voltage. Might try a 6KW charger for a little better conversion ratio but you are not going to do much better than 90%. Internal losses in the converter and the battery due to heating are going to keep you from doing much better.

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