On September 17th, Voyah held a battery safety technology conference at Tianjin Zhongqi Research Institute.
At the conference, Voyah introduced the technical principles of its Amber Battery System, Mica Battery System, and Three-dimensional Thermal Insulation Wall, the five-layer safety protection of battery pack, and Voyah Cloud BMS technology. Voyah also introduced the next generation of battery research and development and supercharging planning.
Dr. Lu Fang, CEO of Voyah, stated at the conference that battery safety has a “veto power” in Voyah’s internal research and development priority.
So what will be the performance of the Voyah battery safety system with the highest priority?
Amber & Mica
Before discussing the Amber and Mica battery systems, let’s first look at the three tests we conducted on-site at the Zhongqi Research Institute before the conference.
Firstly, there was the compression test challenge. Its purpose was to simulate the intrusion scenario after the whole vehicle collision. A rigid semi-cylindrical body with a radius of 75mm was used to compress the battery pack with a force of 200 kN (the national standard is 100 kN) and maintained for 10 minutes. According to the explanation from the on-site staff, Voyah has tested a lot of positions on the battery pack with compression tests.
In the simulated collision test, after a short energy storage, the battery pack was impacted with an acceleration of 50 g / 60 ms (the national standard is a maximum of 28 g / 60 ms). The purpose was to test the performance of the battery pack under simulated impact acceleration.
Finally, we conducted a high-temperature and high-pressure water splashing test to simulate the scenario of high-temperature and high-pressure car washing. The battery pack connector was subjected to water flow with a temperature of 75℃ – 85℃ and a pressure of 10 MPa for three minutes. What is 10 MPa? For example, the high-pressure water gun in a car wash room is generally 3 – 5 Mpa. And the test targeted the interface of the power battery, and there was no water ingress after three minutes of water flow impact.
So how did Voyah do in battery safety with the Voyah FREE?At this press conference, LanTu announced the “Amber” and “Muscovite” self-developed battery system technologies. According to Dr. Huang Min, the Director of LanTu’s New Energy Technology, the “Amber” battery system technology is applied to LanTu FREE electric vehicles, while the “Muscovite” battery system technology is applied to LanTu FREE extended-range version vehicles.
The difference between the two lies in the material and structure of the 3D insulation wall. The “Amber” technology adopts organic silicon composite material to fill the battery pack, which combines organic silicon polymer with low-density insulation material and flame retardant. The organic silicon polymer has good insulation performance, corrosion resistance, and insulation performance. In combination with low-density insulation material and flame retardant, an efficient insulation, flame retardant and insulation layer is formed, allowing each cell to be fully wrapped like “Amber,” hence the name.
“Muscovite” is an insulated flame-retardant protection layer made by adding layered AI-Si mica and aerogel to the battery pack. In addition, LanTu also equips a liquid cooling system at the bottom of each cell to help with sufficient cooling.
In addition to protecting the cells, LanTu has implemented more comprehensive protection measures on battery packs in passive and active safety.
Dr. Huang Min said at the press conference, “LanTu does not produce cells, and we focus more on solving battery system safety problems.”
The first step in solving battery safety issues should be protection.
To protect the battery and prevent damage to cells, the vehicle body has made the first line of defense for the battery. LanTu’s FREE vehicle body adopts high-strength steel with a share of 75%, of which more than 31% has a strength of more than 1500 MPa. The B-pillar and door frame are made of 1500 Mpa ultra-high-strength steel, while 2000 MPa ultra-high-strength steel is used on the collision beam. Of course, for a mid-to-high-end SUV, this should be just a passing grade.
Behind the first defense line of the vehicle body is the battery pack frame. When the battery pack is subjected to external impact, the high-strength aluminum alloy frame is used, together with multiple reinforcing ribs, to form a battery shell protection. In addition, there are two cross members and one longitudinal reinforcement beam inside the battery pack for protection, which can effectively decompose collision pressure. According to LanTu officials, this can allow the battery pack to withstand up to 20 tons of compression without any safety incidents.In addition, LanTu has pre-set over 30mm of deformation energy absorption space for the battery pack to absorb the compression impact at the end during collisions to protect the internal battery core.
Furthermore, LanTu has adopted a double insurance of explosion-proof valves and fuses for its battery core. Even if a short circuit occurs due to intrusion into the battery pack after a strong impact, the double insurance can immediately start its protective function, cutting off the short-circuit circuit in the battery and releasing additional pressure to avoid ignition and explosion of the battery core.
Apart from these five layers of protection, LanTu has also employed a three-dimensional heat-insulated wall technology, which encases each battery cell three-dimensionally to create a heat-insulated, flame-retardant, and insulated protection layer between and around the battery cells. As we all know, fires or explosions of batteries usually occur because a single battery cell catches fire and causes a chain reaction to the surrounding cells, ultimately resulting in thermal runaway of the entire battery system. The three-dimensional heat-insulated wall acts as a “safe compartment” for each battery cell, even if a fire breaks out, it will not affect the surrounding cells.
In other words, LanTu’s five-layer safety protection for the battery pack includes the body, battery pack framework, reinforced beams inside the battery pack, deformation energy absorption space, and double insurance for the battery core. The three-dimensional heat-insulated wall is added to encase the battery cells, forming LanTu’s “passive safety” for the battery pack.
So what is “active safety”?
LanTu has developed remote power battery data analysis and management technology, the LanTu Cloud BMS, in collaboration with its partners. The LanTu Cloud BMS has four major functions, which include infinite hardware calculation power and software upgradability in the cloud, not just remote data collection and monitoring but also battery diagnosis and control based on big data algorithms learned from a vast amount of vehicle data.
The LanTu Cloud BMS has four key characteristics. The first is calculation power, which can currently provide online services for one million vehicles simultaneously, with a response time of less than one second for over 95% of the time, capable of performing calculations and permanent storage of PB-level data, and with data reliability reaching 99.99%.- The second point is early warning. Through building a cloud-based fault monitoring model, Voyah Cloud BMS can analyze up to 108 battery characteristic parameters. Based on battery historical operating conditions and real-time data, through big data platform analysis, diagnosis, and early warning of battery failures, it can achieve 7*24 hours online tracking and push safety warnings on potential battery system anomalies through the APP, allowing for an average of 2 hours advance warning on serious accidents such as smoking or fire, and a week’s advance warning on potential faults such as undervoltage, overvoltage, or internal short circuits.
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The third point is care. Voyah exclusive cloud BMS has established a battery health evaluation system based on users’ actual use conditions, charging and discharging rates, and other dimensions. Currently, Voyah can achieve an accuracy rate of 95% in predicting the remaining service life of batteries with 80% and 70% of life remaining. It can provide users with the optimal battery maintenance advice, and extend the service life of the battery system.
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The last point is self-learning. With more vehicles and longer use time, Voyah Cloud BMS’s fault prediction and health prediction models can continually optimize model parameters and improve prediction accuracy.
For “active safety”, besides NIO’s battery swapping system, there are not many electric vehicle companies currently doing this. In recent foreign media reports, the news of the 2013 Tesla Model S P85 battery swap was mentioned. Tesla’s official after-sales cost for replacing the entire battery pack is $22,500, and the owner eventually spent $5,000 on replacing two modules with third parties, which shows that the cost of replacing batteries is still relatively high.
It is absolutely a good thing for consumers to have online monitoring of battery safety like Voyah. It is not only detecting battery failures, but also evaluating the battery health system. When a certain module of the battery has problems, it can promptly inform the driver, avoiding larger safety hazards. After all, cars are not disposable items, and many people drive them for 10 years or more. Long-term reliability is precisely what consumers need.
Through Voyah Cloud BMS, Voyah has achieved “active safety”, and combined with Voyah’s five passive safety measures for battery PACK, it has passed 80 major and 150 minor tests, including simulating user driving scenarios, fire, compression, temperature shock, vibration shock, bottom ball impact, cooling liquid leakage, and other tests.
Outside the laboratory, Voyah has accumulated over 3 million kilometers in road durability testing, and has undergone extreme environmental testing such as extreme weather conditions of minus 40°C and high temperature of 50°C for the entire vehicle and battery systems.
In ConclusionAt the press conference, LanTu demonstrated the research and development of the next-generation battery and the planning of supercharging. The first-generation fast charging pile will be available soon, which can charge 60% in 20 minutes. The charging time of the second-generation supercharging pile will be reduced to 10 minutes and provide a driving range of 400 km. Additionally, LanTu’s future models will also incorporate 800 V electronic architecture and SiC silicon carbide technology.
In terms of battery research and development, LanTu’s next-generation battery technology will achieve an energy density of 330 Wh/kg. Meanwhile, LanTu has stated that solid-state batteries have been included in the commercial development schedule.
Currently, LanTu has completed multi-layer protection from the inside out for the battery, which has achieved good results in testing. Next, it is necessary to wait for LanTu to deliver the large quantity of FREE vehicles to verify the results over time.
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.