China's 2023 Electric Vehicle Forum: Insights on Battery Efficiency and User Convenience

Hosted by the China Electric Vehicle Hundred People Association, and co-organized by Tsinghua University, China Society of Automotive Engineers, China Association of Automobile Manufacturers, China Automotive Technology and Research Center, and China Automotive Engineering Research Institute, the China Electric Vehicle Hundred People Association Forum (2023) was held in Beijing.

The forum invited representatives from government departments and leading enterprises in the automotive, energy, transportation, urban, and communication sectors to discuss various topics, such as the global automotive industry development trends, high-quality development paths for new energy vehicles, China’s intelligent connected vehicle development strategy, trends in the development of core industry chains like power batteries, new-generation automotive consumer trends, strategies for the coordinated development of automobiles and energy, novel transportation energy security systems, commercial vehicle transformation directions, innovative paths for the automotive aftermarket, and digitalization and smart manufacturing in the automotive industry.

At the 2023 China Electric Vehicle Hundred People Association Forum, Shen Fei discussed the following points in his speech:

  1. A better charging experience, including duration, operational convenience (e.g., not having to get out of the car or plug and unplug the charging gun), and automation;
  2. High battery utilization efficiency, such as flexible on-demand leasing and capacity upgrades;
  3. Battery swapping stations can perform battery safety checks for improved security;
  4. The possibility of interacting with the electrical grid.

Below is the original text of the speech:

Hello, today I will briefly report to you what we have done in the field of serving private car users. We are working on the issues mentioned by leaders and experts earlier, combining the characteristics of our battery swapping and private cars. I will share with you two main aspects. In the first part, I will introduce our overall situation with some data, and the second part is to focus on sharing the interpretation of battery swapping.

As of today, we have more than 320,000 cars that have traveled a cumulative 9.4 billion kilometers, reducing 620,000 tons of carbon emissions, all thanks to our efforts in establishing a self-swapping network. We found that once electric vehicle users resolve their range anxiety and the convenience of charging or swapping batteries is available, they are more willing to drive because the driving experience is more comfortable. With the assistance and autonomous driving capabilities, as long as users are free from anxiety, they are much more willing to use electric vehicles for transportation. So, our general statistical data shows that once users switch to electric vehicles, their travel distances tend to be slightly longer than when they used to drive fuel-based vehicles. We have an integrated charging solution for all scenarios in the background. For us, whether it is ultra-fast charging, battery swapping, home charging piles, or even destination-based charging in parking lots, we will provide the solution. This is our definition of a comprehensive charging solution, tailoring to users’ needs at different locations and situations. We believe this is the best user experience for electric vehicle owners and sets charging electric vehicles apart from refueling traditional vehicles.In terms of overall strategy, our strategy since the end of 2015 has focused on seven words: “rechargeable, swappable, and upgradable”. The goal is to make recharging more convenient than refueling. To achieve this, we’ve employed various measures and created an indicator called the national average monthly charging duration. Since 2018, we’ve reduced this from over 300 minutes to just over 100 minutes, with a target of bringing it down to 60 minutes within two to three years, essentially equivalent to the time conventional fuel vehicle users spend refueling each month. This time includes the users’ travel duration, and we continuously monitor this indicator to hopefully achieve our goal through concerted efforts.

Considering the importance of home charging, we’ve installed 180,000 home charging stations for our more than 300,000 customers. Although some users may not have the option of home charging due to our battery-swap system, we still strive to accommodate these users. However, even without a home charging station, they can still drive their vehicles. We’ve also installed over 14,000 public charging stations – the most among vehicle manufacturers – including fast and destination chargers placed along tourist routes, as well as efficient AC/DC chargers at workplaces. Our infrastructure strategy significantly differs from those of other operators, as we’ve combined our charging stations with our battery-change stations to cater specifically to mid- to high-end personal vehicles. Although locations such as Inner Mongolia and Northeast China may not have been valuable in terms of operations, we’ve installed numerous stations in these areas so users from various locations can drive electric vehicles worry-free. We’ve implemented fast-charging solutions in regions like Heilongjiang as well.

In areas with many EV users, we’ve established battery-swap stations, while in less-populated regions, charging stations predominate. Furthermore, to encourage the use of electric vehicles in the Northern provinces where lower temperatures hinder the user experience, we’ve granted users in these areas an annual allowance of 1,000 kWh of free charging.From the data, currently over 80% of the electricity in our charging stations comes from third-party brands. Based on the backend analysis, this percentage represents the market share of third-party brands. We are continuously contributing to the industry. We have connected 52 Power Up Plan destination charging routes, covering the most famous 52 tourist spots in the country, including routes in Western Sichuan, Sichuan-Tibet, the unique highway, Jilin’s Changbai Mountain, and southern Jiangnan’s Taihu Lake area. With over 1,326 battery swap stations built, users can travel without worry. Up until now, we have also established 13 battery swap stations in Europe. An interesting data point is that since our vehicle delivery began in June 2016, the electricity usage from swapping batteries has exceeded 50%, with a stable average of around 56%. The acceptance of this service is growing among users. Our battery swap service has been used nearly 20 million times, and we expect to surpass that milestone in the next few days.

We have also introduced a concept called “electric area housing coverage,” which refers to the percentage of users who can find a battery swap station within 3 kilometers from their home or workplace. Currently, the national average is 70%, meaning 70% of future users will have access to a battery swap station within 3 kilometers. In cities with a high user concentration such as Beijing and Shanghai, this figure is close to 90%. With big data analytics and the support of our partners, users can utilize battery swap stations as conveniently as gas stations.

We have also done additional work on highways. To date, we have built a high-speed battery swap network covering five north-south and three east-west lines with eight major city clusters. Our goal is to complete a nine north-south and nine east-west network with 19 metropolitan circles by around 2025. These stations have been well-received, with the number of daily swaps during this year’s Spring Festival reaching up to 170 per station. The battery swap network is now fully connected in provinces such as Zhejiang, Hubei, Shandong, Anhui, Henan, Hunan, and Hainan, with stations approximately every 150-200 kilometers.

One unique aspect of battery swapping is the ability to provide battery upgrade services, with a cumulative 60,000 battery upgrade services provided so far. Users who typically use a standard 75 kWh battery in the city can have it temporarily replaced with a 100 kWh battery at battery swap stations for longer trips, and eventually even a 150 kWh battery. This upgrade allows users to save money, as they only need to pay more for the larger capacity battery when necessary, meeting their long-distance travel needs.A greater significance lies in the significant savings in battery resources for the entire industry and society. Instead of each user carrying a long-range battery on their vehicle all day, resource utilization efficiency has been greatly enhanced across society. For example, during this year’s Spring Festival, about 14,000 users upgraded their 70 or 75 kWh batteries to 100 kWh batteries for going back to their hometown or for traveling. However, I didn’t have that many 100 kWh batteries in my system initially. More than 5,000 of the 14,000 batteries were rented back to us by long-range users who weren’t traveling far during the holidays. Then, we rented these batteries to users who needed them. This highly activated and improved asset efficiency is attributable to our battery upgrade service.

Overall, we have defined a scenario called convenient charging. In comparison to fuel vehicles visiting gas stations specifically for refueling, electric vehicles can charge or swap batteries where they park due to the ubiquity of power grids. Therefore, we call it convenient charging. Battery swapping is as convenient as refueling, with home charging, on-the-way charging (e.g., during business meetings or shopping), and a unique one-click charging service. These four charging methods account for around 90% of total power usage. In these 90% of scenarios, charging is now more convenient than refueling. We still have 10% of scenarios where users specifically visit charging stations, which might take more time. Next, I’ll focus on the advantages of battery swapping. As ultra-fast charging is rapidly developing and we’re also launching our ultra-fast charging, we are often asked about the future value of battery swapping. Will it maintain any advantages given its charging time of five or ten minutes? Let’s examine its benefits from various perspectives.

First, from the charging experience perspective, a single battery swap takes about two and a half minutes, plus parking and positioning, totaling about five minutes. This is more convenient than refueling. Second, from the users’ perception, the entire battery swapping process is fully automated and highly intelligent. There is no need to exit the vehicle or handle charging cables in wind or rain, which offers a better experience than both charging and refueling and is particularly more user-friendly for women. Third, regarding the efficiency of battery swapping stations, they are primarily 1.6 to 2 times more efficient than ultra-fast charging stations, especially for the integrated charging and swapping stations. The reason is that battery charging can commence as soon as a battery enters the swapping station, whereas charging only starts when the vehicle is connected to the charging station. In both cases, charging or swapping effectiveness ultimately depends on how much power the power grid can provide. Thus, charging and swapping are decoupled in terms of time. When a vehicle arrives, the station focuses on charging it, and when there are fewer vehicles or none, it charges the batteries in the swapping station. This efficiency will only increase as more batteries enter swapping stations in the future.In terms of battery usage efficiency, first, there is no need for a one-time payment when purchasing a car, as costs can be paid per use, reducing the barrier to vehicle ownership. Batteries can be flexibly upgraded on demand, without paying for unnecessary battery costs. Based on our calculations, at least 17% of battery resources can be saved; not all users need to buy the long-range battery, thus resulting in this level of savings. If the battery is non-replaceable, different users have varying ranges and battery wear; however, after balancing through the current battery swap system, battery efficiency is still improved. All batteries in the system can be depleted along the same curve, greatly increasing efficiency. Furthermore, each visit to a battery swapping station enables a thorough safety inspection, ensuring better battery safety. With battery swap stations available, we completely decouple battery life from vehicle life, making battery recycling more feasible. Based on our observation, if the power batteries in the entire battery swap system can be fully utilized, the proposition for secondary use or disassembly for reuse becomes almost non-existent, as we aim for maximum use within the system.

From the perspective of grid interaction, we mentioned many topics, such as orderly charging, V2G, virtual power plants for grid regulation, etc., all of which we are working on. We divide this into two parts; the first is the simplest one. Since battery swap stations are similar to energy storage, we fully utilize the nighttime to charge all batteries, and during the day, we strive to use flat electricity rates to avoid peak and sharp rates, saving on electricity costs. We can perform peak load shifting and frequency regulation, helping to build a renewable energy-centric power system. At present, dozens of battery swap stations in Zhejiang have been directly connected to the provincial power dispatch center through virtual power plants, and in recent years, we have been participating in demand-side response in North China, Shanghai, etc. We also cooperate with the State Grid for projects such as V2G charging and discharging, which have been piloted and demonstrated for about three years, with some users still using it every week. We utilize our battery swap system in areas where local power capacity is insufficient, such as when it is only 200 kW, by asking some users to help charge their batteries at home and then deliver them to swap stations. All these aspects are part of our definition of grid interaction, and we are working on them.

Overall, battery swapping has many advantages over charging, with four dimensions and ten benefits that have been mentioned. We will continue to explore whether there can be higher systemic efficiency, and we believe that, regardless of the development of fast-charging technology, battery swapping will always provide unique value as it enhances systemic efficiency.Finally, we recently launched NIO’s third-generation battery swap station, which features a 20% faster swapping speed compared to the second generation. The station’s battery capacity has also increased from 13 to 21 battery modules, equivalent to a 2-MWh energy storage capacity, making our interactions with the power grid more valuable. Simultaneously, we quickly introduced the 300-kW ultra-fast charging system with a peak current of 660 A. A third-generation station is equipped with two 500-kW ultra-chargers and two 200-kW ultra-chargers, with the possibility of adding lower-power charging stations if needed. We highly recommend this integrated charging and swapping solution as the ultimate charging solution, ideal for both highway service areas and urban locations. It ensures optimal user experience, efficiency, and utilization of grid power capacity, etc.

Due to time constraints, I’ll keep this brief. We hope to work together to enhance the driving experience for our customers and promote industry development. Thank you all!

This article is a translation by ChatGPT of a Chinese report from 42HOW. If you have any questions about it, please email bd@42how.com.