How is the Battery Charge [Meter] calibrated?

[ElectricTroy]

Is this correct?


_ 90%
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- 60%

[Foxpaw]

Not sure what you mean, but the BCM will only charge up to 80% and down to 20%. Hence, 80% could be considered "full" and 20% could be considered "empty." Because you can't use the top 20% or the bottom 20%, the effective capacity of the pack is 60% of it's actual capacity.

[ElectricTroy]

I was talking about the meter.


The Honda really uses 20-80% of the battery? That doesn't seem smart. Seems like it would cause undue stress. Toyota uses a much, much smaller range (50-80% I think).

[Foxpaw]

20%-80% isn't that bad of a range. It's only 60% of the total capacity, nowhere near a deep cycle.

I suspect the Toyota uses a similar range, though it has a "center seeking" charge where it uses electric more aggressively at high charge and charges more agressively at low charge. Since the "center point" on the Toyota is 56% (I think) I find it unlikely that 50% would be the lower range.

Hi ElectricTroy:

___ANL and NREL (the government labs) have quite a few studies and details on the packs of the Insight and Prius’. I would suggest that you start there because there is quite a bit to learn about actual pack SoC’s vs. what the meters are displaying. Both Honda and Toyota are conservative with a 20 - 80% on the pack is ~ = 0 and 100% on the SoC meters.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:1xgvmhoj]Waynegerdes@earthlink.net[/email:1xgvmhoj]

[ElectricTroy]

I've always been told, for the last 4 years, the Battery Meter only shows the *useable* range (20-80%), not the whole capacity.



Also I've read john1701a's literature. Toyota limits to a range of (quoting from memory) 40-70%. Seems to me Toyota's design is "smarter" since it causes less battery stress.

Troy

[Tim Maddux]

There's a tradeoff between battery stress and loss of available capacity. You could go to 40%-70% but then to maintain the same pack capacity you would have to add weight - more batteries.