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.

Fan Assistant

Introducing the new Fan Assistant

The Fan icon is now a 3-state toggle; every tap will rotate between:
OFF - fan controlled by the car
MANUAL - forced ventilation
AUTO - Hybrid Assistant will turn on or off according to temperature

The Fan Assistant can help you keep your HV battery in an optimal temperature range.
If the battery is too hot, the fan will spin to cool it down.
If the battery is cold, and the cabin temperature is hotter, the fan will spin to heat up the battery.
This feature is primarily meant to be used in really cold climate areas, where a pre-ignition heater is installed in the car.

Warning: the fan control feature is not approved or validated by Toyota. Hybrid Assistant and its development team can't be held responsible for any inconvenience that may related to its usage or misusage. Use it only with high quality OBD adapters and at your own risk.

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

12V Auxiliary Battery Measurement

The new version of Hybrid Assistant checks Auxiliary Battery Voltage while the car is off.

Be sure to use an high quality OBD adapter to have a reliable reading.

Auxiliary Battery Voltage

The new version of Hybrid Assistant allow measurement of the 12V Auxiliary Battery also.

Here is the procedure:

1. Do not turn on the car: just wake up the OBD adapter from sleep. This is accomplished on my car by just opening the driver's door.
2. Run Hybrid Assistant and let it connect: it will display "Waiting for the car" in the status line.
3. After a couple of seconds a panel will open with the 12V measure updating over time.
4. Once you bring the car to READY, the panel will close and operations will proceed as usual.

Please note that Auxiliary Battery Voltage reading works even with the car completely off.
The reading is available as soon as the adapter wakes up from standby.
This is one step beyond the measuring method that uses the hidden menu of the Toyota Touch, because it still needs the car to be at least in accessory mode, and the voltage reading is somewhat altered because of the Toyota Touch load itself.

CCL and Brake

The new version of Hybrid Assistant displays real time CCL and DCL indicators on the HV Powermeter.
Charge Current Limit and Discharge Current Limit shows maximum power that the HV battery can sustain any given moment.
Their value is affected, among other factors, by temperature and battery charge level.
When the battery can not accept any more incoming current, CCL is decreased accordingly even to zero: in this condition, regenerative braking isn't possible anymore so friction pads kick in.
You can see it in this annotated video.

Sneak Peek

The battery diagnostic module is coming...