EV Li-ion Battery Maintenance

Pretty much all PHEVs limit charge to ~80% and prevent discharge below ~20% anyway in addition ot not having quick charge capability so most of this isn't really applicable.

 

Of note, they recommend "read your owner's manual..." Here is the Prime owner's manual discussion about capacity reduction on the traction battery. Note that Toyota recommends leaving a low level of charge in the traction battery when not driving vehicle for a long time. This conflicts with the ZEOG recommendation to leave at 50-60% charge.

 

not all li-on chemistry is created equal

 

That's only true to Prius Prime.

For example, Hyundai Ioniq plugin has a 8.9kWh battery, with 119 MPGe, and 29mile EV range, electricity per full change is 8.2kWh out of 8.9kWh capacity, and capacity usage is 92%. While for PP, 25 mile EV range with 133 MPGe, it is 6.3kWh out of 8.8kHw, capacity usage is 72%.

So Prius Prime has 28% capacity reserved while Hyundai Ioniq plugin has only 8% reserved. Capacity reserved played a important role in battery life or capacity lose and PP definitely has advantage.

EV number is very misleading IMO, MPGe is much more meaningful.

 

Your statement is patently, provably untrue.

The Gen 1 Volt (aka pretty much the highest sold PHEV of all time) limits the ~16kWh battery it carries to about 10 kWh so ~3kWh (18.7%) on top and bottom, respectively.

Given that I've seen more Ferrari 488s than Ioniq PHEVs (or any other kind of PHEV outside of the Prime and Volt), I'd argue that my statement of "pretty much all PHEVs" stands.

 

I did not calculate for Volt G1, but I did calculate for Clarity and Volt G2, they both have much less reserved capacity than Prime.

 

Does anyone know if the engine should be charging the battery in HV Mode? I’m cruising on the highway at 70 and I notice my charge on battery goes up from 20% to 21%. I wasn’t in Charge mode.

 

If you release (or even press lightly) gas pedal, the battery get charged.

 

In Charge Sustainment (HV) mode the engine always tries and recoup what is requested of the Battery via climate control and/or DC-DC converter (lights, wipers, fans, etc.). It tries to make an educated guess about how much is required. So you might see a swing of 1 or 2 MPG plus or minus during a trip.


Unsupervised!