BYD has adopted a self-sufficiency strategy by boosting in-house design and system assembly
Twice a month, Yole SystemPlus analysts share the noteworthy points from their automotive Teardown Tracks. Today, Benjamin Pussat, Technology & Cost Analysts at Yole SystemPlus, part of Yole Group, takes us to the heart of BYD’s all-in-one high-voltage powertrain, the most integrated electrification system on the market.
From the stand-alone units of 10 years ago to today’s most commonly used 3-in-1 Integrated Power Unit and e-axle, BEV high-voltage integration continues its unbridled progress. On this point, Chinese OEMs are at the helm. Chang’an and Leapmotor already offer 7-in-1 systems. BYD goes a step further by additionally embedding the BMS (battery management system) in the box(1). Thanks to strong incentive policies followed by penalizing regulations (dual-credit mandate), the share of EVs reached 27.6% in China in 2022 whereas it was 0% a decade ago.
Highlights from Yole SystemPlus Automotive Teardown Tracks
The BYD 8-in-1 powertrain includes the BMS, VCU, inverter, PDU, OBC-DC/DC merged into one unit, and the gearbox/e-motor in another. The teardown was performed on all devices apart from the gearbox and e-motor.
Yole SystemPlus observed that the overall system space is optimized, with components placed very close to each other, and sub-boards soldered perpendicular to the OBC/DC-DC power board. This involves the implantation of an efficient thermal management solution characterized by the use of SiC technology for both inverter and OBC-DC/DC MOSFETS, thermal pads placed over critical areas, an insulating sheet and a water-cooling system.
Eleven boards were discovered. Four are used in the inverter area, the other ones in the OBC/DC-DC. Main component identification reveals that BYD still relies on foreign providers for most of the electronic components (led by Texas Instruments). However, local suppliers such as Runic, Len Technology, Novosense and Faratronic provide basic functions components.
Opening the system makes it clear that the Chinese OEM has adopted a self-sufficiency strategy, as most of the key power components have been identified as being manufactured or assembled by BYD (inverter SiC power module, output current sensor module, power relays, DC link capacitor…). This certainly helps the company to lead the total integration race.