BYD India has launched an all-electric MPV e6 for the Indian B2B segment with its 71.7 kWh Blade Battery that claims a WLTC city range of 520 km. BYD's marketing message about its blade battery is that it’s the safest battery around. In this write-up, Rahul Bollini discusses some of the featur Contact online >>
BYD India has launched an all-electric MPV e6 for the Indian B2B segment with its 71.7 kWh Blade Battery that claims a WLTC city range of 520 km. BYD''s marketing message about its blade battery is that it’s the safest battery around. In this write-up, Rahul Bollini discusses some of the features and advantages of this battery.
While undergoing nail penetration tests, the Blade Battery emitted neither smoke nor fire after being penetrated, and its surface temperature reached 30 to 60°C. Under the same conditions, the NMC battery exceeded 500°C and violently burned, and while a conventional LFP block battery did not openly emit flames or smoke, its surface temperature reached dangerous temperatures of 200 to 400°C. This implies that EVs equipped with the Blade Battery would be far less susceptible to catching fire, even when severely damaged.
The Blade Battery also passed other extreme tests, such as being crushed, bent, heated in a furnace to 300°C and overcharged by 260%, without resulting in a fire or explosion. It also completed a strength test that saw it being rolled over by a 46-ton heavy truck which it passed without leakage, deformation or smoke, coming out intact and ready to be used in an EV.
In April 2021, BYD announced that all of its pure electric vehicles would come with the Blade Batteries, with nail penetration testing adopted as a brand standard. The first batch of BYD’s sedan HAN EV recently arrived in Brazil, Mexico, Colombia, Uruguay, the Dominican Republic, Costa Rica and the Bahamas. Han EV comes with a range of 605 kilometres and an acceleration of 0 to 100km/h in just 3.9 seconds. e6 launched for India’s B2B market is also equipped with the Blade Battery.
A negative chain reaction due to high pressure and high temperature causes thermal runaway in a Lithium-ion cell. Since NMC cells release oxygen as a by-product during thermal runaway, they tend to catch fire very easily. On the other hand, there is no oxygen by-product released in LFP cells during its thermal runaway and hence they don''t catch fire.
NMC cells are preferred in EVs because of their higher volumetric density, which allows for higher energy to be stored, enabling a higher range of electric vehicles. BYD blade battery has a higher volumetric energy density compared to regular block type prismatic cells. Hence, the BYD blade battery has enabled the usage of LFP cells in long-range electric vehicles while addressing safety concerns of catching fire during an incident of thermal runaway.
Using a higher number of smaller capacity regular block type prismatic cells create a mechanical disconnect in a battery pack and leads to less efficient utilization of the space. Regular block type prismatic cells have to be packed as a module first and then the modules are assembled into a final battery pack.
On the other hand, BYD blade cells allow for direct cell to final battery pack assembly, eliminating the need to assemble into modules and increasing the overall volumetric energy density of the final battery pack. The singular cells are arranged together in an array and then inserted into a battery pack. Due to its optimized battery pack structure, the space utilization is increased by over 50% compared to conventional LFP block batteries.
My LG Chem 6.4 kwh battery has got to a stage where I can no longer reset the battery.Is there any chance of getting it repaired, by replacing faulty cells? Battery world think that it is out of their league.Can you give any suggestions please
"It''s given my wife and me pause," said Kevin Whittle, a Farmington, Michigan-based industrial automation consultant. "We were looking at various electrics, not at Bolt specifically. But EV fires and the recall concern us. We just don''t trust the tech yet." Whittle mentioned that his confidence in buying a new EV was further sapped when he saw an online video that showed a sign in a San Francisco public parking lot. It read: "For customer safety: CHEVROLET BOLT EVs are STRICTLY PROHIBITED from parking at this facility. Thank you for your compliance!"
"The batteries in those EVs use NCM, or nickel-cobalt-manganese, cathodes," explained Dr. Zhong (John) Chen, project manager of vehicle engineering at BYD''s northern California headquarters. "With NCM you can easily get a fire. Users of that chemistry have to put a lot of effort behind thermal management and safety, adding cost."
Enter lithium-iron-phosphate (LFP; LiFePO4), a proven chemistry whose benefits were somewhat bypassed by the industry''s settling on lithium-ion cells dominated by NCM, experts note. Where LFP cells shine primarily is in their inherent stability, typically sacrificing some energy density versus NCM for resistance to thermal runaways. At approximately 200 Wh/kg at the cell level, they''re about 10-15% less energy-dense than most NCM cells (Tesla''s 2170s are rated at over 260 Wh/kg).
"LFP batteries are probably most notable for their positive safety profiles relative to other chemistries," noted Guidehouse Insights research analyst Maria Chavez in a May 2021 report. The chemistries "are generally thermally and chemically stable—plus, the phosphate chemistry has been shown to offer a long lifetime," she stated.
LFP batteries have demonstrated life cycles in excess of 10,000 cycles, or millions of highway miles. They exhibit lower internal resistance than NCM types, enabling faster power delivery for improved vehicle acceleration. Discharge voltage of LFP is very consistent. Strategically, their chemistry does not include cobalt or nickel. And the lack of those metals makes them inexpensive, with LFP costs under $100/kWh in China.
That cost advantage has prompted Tesla, Ford and Volkswagen to announce a shift to LFP cathodes in order to move away from cobalt and nickel. This is both for ethical/mining reasons as well as to offer significant cost reduction for some EV models that do not require high performance and +200-mile driving ranges (that will be covered by high-manganese content lithium battery chemistries with higher specific energy). Ford, however, has indicated that LFP cathodes may also end up in the batteries of its electric F-Series.
Going beyond the CTP concept, BYD recently showed a new battery concept called CTC (cell-to-chassis). In CTC, the inherent safety of the LFP chemistry enables the Blade batteries to be integrated directly into vehicle body structure. BYD''s ''e-platform 3.0'' is a special pure electric vehicle structure that uses the battery to increase the rigidity of the vehicle.
BYD engineers and chemists began work on the CTP Blade concept about three years ago, Chen said. It was purpose-designed for automotive, to give BYD a competitive weapon against NCM''s superior energy density and cold-weather performance. "We have a big stake in the LFP technology so we sat down to determine how we can compete with NCM, particularly NCM811 which is "a big competitor" to the Blade battery.
The 811 number of the nickel-rich layered oxide NMC811 denotes 80% nickel and 1% each cobalt and magnesium. While the chemistry offers high specific energy density for EVs, its downsides include rapidly-depleting capacity and voltage, battery experts note. In terms of chemistry, "there isn''t a lot of innovation you can do in a short time," Chen said. "We did patent the cell structure and mainly focused on structure optimization. After a thorough analysis, we decided to remove the module level; that was the main breakthrough."
Viewing an LFP battery''s Module level as unnecessary, the engineers removed it. "In doing so we eliminate some mechanical parts, reinforcements, and some harnesses," Chen noted. "With the Blade battery we reduce weight, decrease overall pack volume by about 50 percent, and increase the energy density. This makes a very solid point for our chemistry. It''s more robust than a module-based pack, it''s lighter per cell and it''s about 20 percent cheaper."
A robust designThe accompanying exploded view of the Blade battery shows its simplicity. Typical dimensions of the compact, single-cell design are 905 x 118 x 13.5 mm (35.6 x 4.6 x .53 in.). The size can be customized. The thin, blade-like cells are inserted into the pack in a blade-type array. BYD engineers have also decreased the cubic volume of the battery installation by 50%, improving overall vehicle packaging.
From top to bottom, there is a layer of cotton thermal insulation. Then there is the thermal management, usually liquid cooling. BYD uses a special thermally-conductive adhesive between the cooling system and the cell stack. The third layer from the top is the cell stack. Protective plates are integrated with the battery''s aluminum housing. "It''s a robust design; a lot of cross bars, bus bars. The BDU and BMS [battery disconnect unit and battery management system] are included; we do the integration," he said.
About Byd blade battery chemistry
As the photovoltaic (PV) industry continues to evolve, advancements in Byd blade battery chemistry have become critical to optimizing the utilization of renewable energy sources. From innovative battery technologies to intelligent energy management systems, these solutions are transforming the way we store and distribute solar-generated electricity.
When you're looking for the latest and most efficient Byd blade battery chemistry for your PV project, our website offers a comprehensive selection of cutting-edge products designed to meet your specific requirements. Whether you're a renewable energy developer, utility company, or commercial enterprise looking to reduce your carbon footprint, we have the solutions to help you harness the full potential of solar energy.
By interacting with our online customer service, you'll gain a deep understanding of the various Byd blade battery chemistry featured in our extensive catalog, such as high-efficiency storage batteries and intelligent energy management systems, and how they work together to provide a stable and reliable power supply for your PV projects.
