where did the savings come from?

[Limey]

So it looks like more testing is needed.

This morning I charged to only 80%, well 79% (that's all it ever charged to) and I drove to work normally. Today it took 25% of the battery to get to work! I'll run in at 80% thru the rest of the week to see if that number holds.

 

[Limey]

I'm finding the car is sensitive to other factors such as wind. My own one-way commute energy consumption floats in a range from as high as 42% to as low as 35%. Typically this averages out on the return trip. I noticed the higher consumption days are typically windy (either headwind or crosswind).

I find my one way drain stays within a very tight range, changing about 2-3% at max. I should note, that I have only been driving it for a month, so maybe once we get into windier fall weather I will start to see greater variations.

 

[Limey]

So it looks like more testing is needed.

This morning I charged to only 80%, well 79% (that's all it ever charged to) and I drove to work normally. Today it took 25% of the battery to get to work! I'll run in at 80% thru the rest of the week to see if that number holds.

Today it took over 24%, so it definitely takes more battery for me when I'm not fully charged.

 

[mctom987]

I'm thinking this all can be attributed to the voltage. A fully charged battery is 403V, while a safely depleted (no battery is ever truly 0V) is around 300V.
This isn't a small difference, and to makeup that difference, it usually means a higher draw in amps. Most batteries (including Li variants) are rated for capacity at a small (usually .3C) discharge. At higher discharges, the usable capacity is lower. This is most notable in Alkaline and lead-acid batteries.

 

[Limey]

I'm thinking this all can be attributed to the voltage. A fully charged battery is 403V, while a safely depleted (no battery is ever truly 0V) is around 300V.
This isn't a small difference, and to makeup that difference, it usually means a higher draw in amps. Most batteries (including Li variants) are rated for capacity at a small (usually .3C) discharge. At higher discharges, the usable capacity is lower. This is most notable in Alkaline and lead-acid batteries.

Seems kind of backwards, if it has a higher draw when fully charged, shouldn't it being using it faster?

But I guess that must be the case, cause I charged to 100% this morning and did the 20 miles in 20%.

 

[mctom987]

Dunno, it's pretty complicated.
Maybe it's inaccurately guessing the SOC based on voltage?