More on BYD's new battery and e tech

I wrote about BYD’s incredible Super E Platform earlier this week. As more times go by, we are just seeing how incredible this platform it is.

A week ago, XPeng came out with G6 and G9 SUVs using 800V 5C fast charging batteries across the board. According to some testing of its charging system, G6 charged from 17 to 95% in 18 min on a 720kW charger and also 6 to 95% in 20 min on a 600 kW charger and 7 to 95% in 22 min on a 360 kW charger.

On the other hand, BYD Han L was able to charge super quickly with 120 kW chargers in the cold of winter. Using dual-gun charging, it was able to sustain 230 kW+ speed from 16 to 80% even in super cold weather and maintained up to 150kW even over 90% SOC. It charged fully in absolute cold in just 24 minutes.

There is something about BYD’s battery tech that allows it to charge fast even in cold weather and sustain high speed across the entire curve. Whereas for other 800V and 5C, they can only sustain high charging speed for a short period in ideal weather conditions. As such, their charging time to 95% even with superchargers are about as fast as BYD Han L using regular highway superchargers (typically <= 150 kW).

Why is BYD so good at charging curves? Well, it owns the entire battery and electrical platform supply chain and chips. As it increases R&D, these departments will work together and continue to integrate better. BYD was already really good at heat management, BMS and packing, but it got even better at with YangWang U9 doing all the race track testing at Nürburgring.

Look at all the areas that need to raise to 1000V for the entire car to be 1000V.

And beyond that, BYD is ahead of everyone else with its 1500V chip. As you can see, BYD is producing electric drive Silicon Carbide chips at 750V, 1200V and 1500V+. They can use 750V chips for 400V platform, 1200V for 800V platform.

The SiC module needs to be able to handle higher voltage than the peak voltage of the EV platform. Think about the higher amp (1000A) and temperature vs the current high amps (700A?) which require higher voltage power chip and advanced packaging to control. See below for BYD 1500V SiC able to withstand in 200 C, peak current of 1000A and stray inductance of 5nh.

As such, only BYD right now (not sure about Sany from the diagram) is able to handle 1000V and then 1200V platform. Remember that BYD came out with 1500V max voltage battery electric construction vehicle blade battery last year

And if you look at the chart below from 2023, it is working on driver IC for 1700V SiC power module to be delivered this year. As such, it is clearly ahead of the field in high voltage power modules production, driver IC and packaging.

Another cool thing is that BYD supplier Hunan Sanan group has increased the yield on its 8-inch Silicon Carbide wafers to 95%. As such, BYD’s SiC plants can produce SiC MOSFET at significantly lower cost than before (which typically used 4 or 6-inch wafers). Using domestic equipments and scaling up production also lowered its cost significantly. As such, we can expect all the EVs in BYD’s lineup to go from using IGBTs to SiC MOSFET over the next few years. That will lead to significant improvement in power consumption and efficiency of the lower cost BYD EVs.

One of the industry insiders expect that as it raises the production of the core components needed for this platform, it will be able to put this Platform on 100-150k RMB models in two years. Can you imagine 1000V and 10C charging across the board for BYD EVs? That would be a significant advantage over competition.

According to the same guy, Su-7 used just BYD’s battery cells for its lower priced models (packing was done by Xiaomi?). However, Xiaomi is so impressed by BYD’s BMS and packing tech that it is buying the full pack from BYD for Yu-7. Now, consider that CATL is the world’s largest battery supplier, but a lot of its batteries are supplied through JVs where it is just providing the cells, but not the packing technology or BMS. Think about companies like Tesla that use their own packing and BMS tech.

It’s very impressive that BYD is so advanced in packing, heat management and BMS. It may not be the best in battery cells, but it is the best at cost control, packing cells in compact volume, managing heat and such. For example, just see the photo below on how BYD’s blade battery can effectively dissipate heat and maximize battery volume usage vs square shell battery

Great space utilization, lower cost and still able to handle fast charging

That’s why the blade battery is able to handle fast charging while also keeping the cost down. This is true innovation.