Prime Traction Battery Properties

Yes all of the cells would be charged to 1/3 full. This keeps the voltages from changing substantially and keeps inverter in a very efficient range.


Unsupervised!

 

There might be some additional balancing that happens in the last 20 minutes of charging, when it's at 100% but still using a little power. It's probably a good idea to fully charge it occasionally, maybe once a month.

 

For the Prime it's 95 cells in series that all share the voltage equally. When one or more cells start to have their voltage drop faster than the majority of the rest of the cells it is an indication that your pack is going bad. 0% to 100% state of charge on your dash board is really 20% to ~80% rated state of charge for the battery itself. The Nickle based battery of the regular hybrid cycles around the 50% to 60% SoC range or there about. This is good for the batteries resulting in a long life.

On with the show.

 

just charge it all the way and drive until it needs recharging, you won't hurt anything

 

I can't imagine that StevePea or anyone could be so organized or clairvoyant that he would know that in 5 or 6 days that he will only have to drive 8 miles. At that rate he is putting less than a thousand miles a year on it. I am with bisco - Just drive it!

 

I think we've seen that the dominant aging effect is time, with high temperature the next most important. Cycle count really doesn't seem to count for much. The NiMH batteries in Prius all last about 10 years, whether that means 80,000 miles or 300,000 miles. Sure there are examples of early failure, as well as extreme long life, but they don't track the mileage. Lack of use appears to age a battery faster than heavy cycling. I regard the air cooling used in the Prime as a weak point that could use improvement. Time will tell.

 

This is basically false.



Even through the Prime battery's 0% and 100% correspond to something like 15% and 85%, narrowing the range further definitely increases overall life quite a lot as the above graph shows (compare green which is similar to the Prime's charge cycle) to blue (probably corresponds to not charging above 85% on the Prime meter), purple (corresponds to not discharging below something in the 20% range), and orange above the green line.

 

I charge my battery maybe three times a week to 100%(~85% reality) and drive ~500 miles total every week. So usually the battery is around reality 20%-15%, and I’ve noticed pretty bad battery degradation. I can only put in 5.5kwh into the battery while it started at over 6. I think SOC is critical to battery capacity.

 

lee jay's graph has no basis in reality

 

Please explain the part of it you dispute.

Looking at the range/distribution values, the results make sense.

 

What, do you think I made it up or something?

How about these?

 

Am I to believe that all lithium ion batteries follow the same curve? So a Leaf battery would have the same life cycle as a Tesla battery?

 

You might find this data useful: Prius Prime Plus in my hands | Page 30 | PriusChat

Bob Wilson

 

No, but the curves all have the same basic shape and properties.

 

if it were an issue, toyota would be more specific about charging

 

Or they can have a generous for them battery warranty and make it really difficult to understand how much capacity is left in your battery.

 

absolutely

 

From what I've read, the leaf has no active thermal management for the batteries.
Neither for charging or discharging.

Not a good idea at all.
I don't think that any other car does this.

If the prius battery gets too hot while discharging, it turns the battery cooling fans on max, and quits using the batteries until they cool down.
If they get too hot while charging, the charging turns off until they cool.