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Discussion Starter #1 (Edited)
Honda lists our battery as a 60 Cell Lithium Ion pack. Nominal Voltage for Lithium Ion Batteries is 3.6v. (Most battery manufactures use 3.7v). Fully charged a Li-Ion cell is 4.2V, soft cell cut-off is 3.2V. What does this mean:

Fully charged pack 60x4.2V= 252V
Nominal (50%) = 60x3.7V (conservative number)= 222V
Discharged (Safe) 60x 3.2V= 192V.

The reason for my nerd-ing out was to try and figure out at what voltage were our Electric Motors operating at. I'd be willing to guess that our Insights EV propulsion system is rated at somewhere around 180V.

What I find totally confusing is that the NFPA Service Manual provided by Honda states our HV system is around 270V.

I got this bug in my head when reading about battery mods done to the second Gen insight (roughly 150V system).

Basing this information on our 10-unit battery gauge, each bar represents roughly a 6V change, operating range of 252-192V. If Honda used the 3.6V nominal calculation, then soft cell cut-off = 180V, each bar represents ~7.2V.

I'm sure that I'll expand on this when I get more information.
 

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2019 OWP Insight EX
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Found this in the emergency response guide:

"High-Voltage Lithium-Ion Battery
In addition to a 12-volt battery, the Honda Insight Hybrid has a high-voltage lithium-ion battery located in a well protected area below the rear seat. This means that the lithium-ion battery body is normally hidden from view. The battery pack is made up of 60 cells, totaling approximately 270 volts."

So, that would put the full charge at 4.5v. Maybe they are "magic cells?"

As for the the battery gauge, there could be a ton of wiggle room put in by Honda. A bottomed-out gauge would not necessarily mean soft cut-off was hit. I'd bet they'd put a small margin in.
 

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Discussion Starter #3
Found this in the emergency response guide:

"High-Voltage Lithium-Ion Battery
In addition to a 12-volt battery, the Honda Insight Hybrid has a high-voltage lithium-ion battery located in a well protected area below the rear seat. This means that the lithium-ion battery body is normally hidden from view. The battery pack is made up of 60 cells, totaling approximately 270 volts."

So, that would put the full charge at 4.5v. Maybe they are "magic cells?"

As for the the battery gauge, there could be a ton of wiggle room put in by Honda. A bottomed-out gauge would not necessarily mean soft cut-off was hit. I'd bet they'd put a small margin in.
Correct, all of this is speculation, reinforced with my knowledge of lithium cells. And yes, the only reason I felt safe that a bottomed out gauge could be soft cell cut off is the fact that the car essentially cuts off at ~20% remaining.

I wonder if they specified 270v for first responders due to the ppe requirements of 277v vs 220v. 277v is a whole different animal than 220v.
 

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So, that would put the full charge at 4.5v. [270 volts divided by 60 cells.] Maybe they are "magic cells?"
It's possible that they are indeed magic (high capacity) cells:
"Li-ion with traditional cathode materials of cobalt, nickel, manganese and aluminum typically charge to 4.20V/cell. [...] high capacity Li-ion may go to 4.30V/cell and higher." (Source = https://batteryuniversity.com/learn/article/charging_lithium_ion_batteries)​

Many of the review articles also mention the 2019 Insight is rated at 1.1-1.2 kWh (versus the Clarity PHEV at 17 kWh and Clarity Electric at 25.5 kWh capacity). Is it better to think of the energy measure in power (volts) rather than energy (kWh)... or are both needed for the full picture?
 

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Discussion Starter #5
I'm used to working with single li-ion cells (I'm sure this answer would differ for someone more electrically engineering inclined), and we always work with them in terms of state of charge, (Voltage). So short answer, it's the unit I'm most comfortable with.

Long Answer:
kWh is a tricky thing because it's a good number for comparison, but in all reality tells you very little about what's going on behind the scenes.

kWh= 1000 watts running for 1 hour.
kW= 1000 watts
watts= amperage x voltage.


Trying to decipher how much energy used by our car for one hour of use, would require quite a bit of math with unknowns to account for, for example how many amps of current does our system use under what percentage load.

I don't know the Current of our system, so the unit that makes most sense to dissect for me at this time is Power (voltage). I could figure out more if I used the horsepower conversion, to find out the wattage, leaving the variable of current. Most lithium Ion cells are rated from anywhere from 5 amps of discharge up to 30 amps continuous discharge.
 
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