As the durabilities (power storage) of EV batteries gradually improve to reach the level of ICE vehicles, the era of EVs is around the corner. At this point, charging speed becomes the next technological pain point that EV owners are concerned about. EV charging speeds are mainly determined by the charging power of the charging station (of course, voltage and current will also interact to affect the charging curve), and the vehicle’s triad (battery, electric control, motor) systems need to match correspondingly. Because charging power is the voltage multiplied by current (P = V x I), increasing power means either amplifying one of the two. If the current needs an increase, a larger wire cross-sectional area is required, which will affect the wiring layout within the limited space of the vehicle and also bring up problems with heat dissipation and energy loss. Therefore, the conclusion is that efforts must be made to "increase voltage.” Porsche launched an EV compatible with an 800V charging system a few years ago, ushering in a new era of high-voltage charging platform technology. However, this groundbreaking technology has not become widespread after several years. The road from idea to reality still seems somewhat distant…
Firstly, to achieve high-power charging from 400V to 800V, the vehicle's triad systems, on-board charger (OBC), high-voltage power distribution unit (PDU), DC/DC converter, compressor, battery materials, and more all need to withstand high voltage. Currently, the third-generation semiconductor material, silicon carbide (SiC), can handle high voltage and has become a popular choice for future EV platforms. However, due to the costly production and unstable supply of SiC, Tesla's Elon Musk recently announced plans to develop new technology to reduce SiC usage by 75%. Whether this idea can be successfully implemented remains to be seen, but if not, the goal of widespread adoption of 800V vehicle platforms within the next three years may be hard to achieve.
Secondly, at the charging station end, the vast majority of current charging stations only meet the 400V requirement. Therefore, EVs with an 800V charging system must install a DC/DC booster converter to increase the current from the 400V charging station to 800V. In other words, without quickly increasing investment in 800V charging stations in the charging ecosystem, high-cost 800V EVs will also have difficulty realizing their fast charging advantages.
Despite the challenges of SiC supply, cost, and technical barriers, the 800V platform remains the main force for improving charging and discharging speeds. Currently, besides German car models, Korean and some Chinese self-owned brands have also been mass-producing and launching these vehicles in the past two years. Typically, when the vehicle battery has low remaining power and matches with a compatible charging station, it can achieve a reported range of about 150km in five minutes of charging. Even if the actual performance is 20% less, the ability to travel 120km after just five minutes of charging drastically improves EV’s charging efficiency. I predict that 800V platform EVs will gradually become mainstream after 2025, especially when combined with safer solid-state batteries with larger capacities, which have slower charging and discharging speeds but are expected to complement the weaknesses of the system and become the best combination of the EV energy system around 2028.