EV Battery range

[Flatcoat]

There are lots of discussion and arguments about the various merits of budget priced MG EV’s and the more expensive offerings from Tesla et al. Now I appreciate if your budget only stretches to a ZS or HS PHEV it is still a very good value buy. However does anyone ever ponder why there is such a price difference (putting possible lower labour costs for the MG)? I have been doing a reasonable amount of reading and research on PHEV’s and one key aspect of BEV’s and PHEV’s is battery management. A Tesla is designed to operate between 20 and 80% of the theoretical range of the battery. The logic being to ensure battery longevity and ensure there is - or should be - some back up for emergencies. Similar with the Toyota PHEV. The car will run in EV mode down to 30% battery capacity. After which it turns to self charging HEV mode to retain that 30% for additional power, help on hills etc etc. It still provides a 40+ mile range in pure EV mode. I guess other BEV’s and PHEV’s have some built-in battery preservation too albeit not sure that applies to the HS, ZS and 5? I am not promoting one manufacturer over the other but it might be a consideration for some. It is also arguable the large battery is a waste of resources too. Something to ponder and discuss.

 

[EVsince2016]

All EV batteries are best kept in mid ranges away for high or low states of charge, so 20-80% is recommended for most of the time. On top of this there are further buffers that protect the battery from damage.

Only the LEAF doesn't have a decent BMS and as a result the battery gets seriously hot on rapids.

Most batteries deteriorate up to 10% when new then stay stable with very slow capacity loss.

The exception is the LFP battery which is known as the million mile battery. It has no known limit on use yet. Fitted to MG SR models.

As all batteries for multiple car manufacturers are made by the same bunch of battery manufacturers and blocks of manufacturers share platforms the difference between premium and economy isn't that great. Even Tesla uses Panasonic & CATL batteries, the same CATL batteries in the MG SR.

Tesla has a unique model as it uses multiple chemistries and unique battery forms and has long detailed evidence of battery SOH (state of health).

There is no simple answer as evidence is limited, but overall the battery chemistry is more important than the BMS variations or price of the car.

 

[Coulomb]

The exception is the LFP battery which is known as the million mile battery. It has no known limit on use yet.

The million mile battery is still theoretical. LFP is better than NMC, but it still has a definite life limit.

LFP is popular in EV conversions (converting petrol drive train to electric). A friend has had to replace his original LFP battery after about 12 years of use. It doesn't have thermal management, so the battery life is shorter than a production vehicle. It was also a smaller battery, 28kWh, which works the battery harder.