S6 charging speeds and HV battery care

[fred12345]

Thought it might be useful to keep HV battery info in one place on S6 forum so to start the discussion, post 1 on best practice for S6 NCM HV battery health. Best to start with this - don't worry about it too much! Enjoy the car and charge up to 80% unless 100% is needed for the next day drive.

For those of us who have noting better to worry abut but the battery SoH %, lots of advice out there but the most sensible is that recharging your NMC battery more frequently over a narrow charge range is better for the long-term health of your battery than deeply discharging before recharging. Studies suggest that keeping your battery SoC between 40% and 80% will lead to an improved long term capacity when compared to NMC batteries whose SoC regularly ranges between 10% and 100%.

The Bottom Line​

• Balancing: At least every few months, regardless of battery chemistry, charge your battery to 100% (on an AC charger) and leave it charging after that 100% SoC is reached – until the charger indicates that the battery is no longer drawing any electrical current. Then, for NMC batteries, go for a decent drive the next day, to reduce the SoC to 80 or 90%.
• Charging NMC batteries: Long term battery health is improved for NMC batteries if they are regularly charged to 80% SoC. NMC batteries can be charged to 100% for longer trips, or every few months for cell balancing. Keep the lower regular discharge level to 40%.
• Discharging / Recharging: The long term battery health of NMC batteries will be improved if you top up the battery regularly, rather than deep discharging before recharging. Regular recharging over a narrow charging range is better for NMC batteries than infrequent long charges over a wide charging range.
• Storing: For longer term storage, leave your EV battery charged at 60% – 70% SoC. (for hotter weather, lower SoC is recommended, down to 30-40% apparently)

Article link: evworld.au/ev-charging/ev-battery-cell-balancing/
And for some more scientific NMC info:

 

[fred12345]

So, to charging speeds - managed to get 142kW yesterday.

This was our first longer drive with S6, around 600 miles (~950km) of mainly motorway and A roads at fairly constant 70-ish mph (110-130kmh) and 9 hours drive... First half achieved around 3.3 m/kWh and later with higher speeds 3.1 m/kWh (messed up my "to date" 4.2 average)...
Trip started with 80% charge as I figured out that we would stop after 2.5 hours in any event so ended up charging 3 times, always up to 80%. I think the lowest I went was 25%.

 

[Giller]

Personally, not only with the car but other items which have relevant batteries on board I never charge to 100%, the S6 always at 80% unless we have a long trip planned, I do balance monthly however and top up regularly with surplus solar,