10 Years of battery usage

 My Yaris is now 10 years old: it's time to have a look at its battery:

It's still looking good, with delta between battery blocks under 0.1V most of the time, just a little worse than the 8th year check.

Car usage is mostly urban, so plenty of EV battery depletions, and forced charges, because of slow moving traffic. Open air parking at night also.

On a side note, the 12V battery is still the original one.
I've never had a car with a service battery lasting more than 5 years: probably the periodic CTEK treatment had some benefical effect on that.

170.000 km and counting...

As battery life is always a classic debate argument, here is the HV Check from a long time friend of the Hybrid Assistant development team: his Yaris MY12 is just a few km under the 170.000 mark, and the battery is in perfect shape.
The delta values of the battery modules is really low, and nearly constant both at high and low SOC levels.

 

8 years of battery usage

My Yaris is approaching its 8th birthday and has just passed the 80.000 km mark.

In the last 4 years she has lost her internal garage parking place to her bigger sister Auris, so she also has passed 4 winters and 4 summers under the stars, with no particular care so it's time for an HV check.

Here is a full discharge/recharge cycle chart from Hybrid Reporter:
All blocks discharge uniformly, none of them behave significantly different from the others.

We have further confirm from the Delta chart, where we see that voltage difference is always well under 0.2V, and just above 0.1 at the lower SOC levels.

According to this article, battery is still at near full capacity.

These charts suggest little Yaris has many more years of travel in front of her wheels.

HV Battery Capacity Estimate

During an HV Check, an estimate of the battery capacity is also shown on screen.
All models (except Prius Plus and Prius Plugin) have a nominal 6.5 Ah battery capacity.
To evaluate capacity follow these guidelines:
1) be sure to have at least 60% SOC, engine and battery at operating temperatures (i.e. not too low or too high)
2) park the car
3) start A/C at the lowest temperature, to put some load on the battery
4) be sure the petrol engine is not running and have completed S1 phase
4) start HV Check
5) keep the check running until actual SOC is at least 10% less than the starting SOC

The Estimated Capacity will change color when enough data will be collected.

The same information is present on the report from Hybrid Reporter

Voltage Delta Chart

The Voltage Delta chart plots voltage differences between blocks.
The bottom area plots delta value between maximum and minimum values.
Min, Max and average values are also plotted.
If the average value is not roughly halfway between min and max, we may have a block balancing issue.

HV Battery Temperature Chart

The HV Battery Temperature chart plots temperature sensors values during an HV Check.
Common thresholds (fan and EV disable) are also shown, along with current.

Block Values Chart

The Block values chart plots individual battery block voltage values.
SOC % level is also shown