New energy vehicle range increased by 40%? The dual revolution of magnesium hydroxide electrode materials and electrolyte additives

At a time when competition in the new energy vehicle market is fierce, range and safety have always been the core pain points of users. Recently, a technological breakthrough led by Jiangsu Zehui Magnesium-based New Materials has caused a stir in the industry. By using magnesium hydroxide (Mg(OH)₂) as both an electrode material modifier and an electrolyte additive, the lithium metal battery developed in cooperation has achieved a 32% increase in energy density and a cycle life extension of more than 1,500 times in actual measurements, and a comprehensive range increase of 40% compared to traditional solutions. Behind this "double revolution" is the innovative application of magnesium hydroxide in the fields of materials science and electrochemistry.

1. Electrode material innovation: dual breakthroughs in high-stability positive electrodes and lithium dendrite suppression

1. "Structural stabilizer" of positive electrode materials

As a positive electrode material additive, magnesium hydroxide combines with traditional materials such as lithium iron manganese phosphate through solid-phase reaction to form a nano-scale composite structure. This design not only improves the conductivity of the positive electrode, but also reduces the volume expansion rate of the material during charging and discharging to 1.2% (5-8% for traditional materials), thereby significantly reducing the capacity decay caused by structural collapse39. Experimental data from Zehui Company showed that the discharge capacity of the positive electrode material with 5% magnesium hydroxide added jumped from 180mAh/g to 240mAh/g, and the energy density increased by more than 30%9.

2. "Firewall" of lithium metal negative electrode

Constructing a magnesium hydroxide coating on the surface of the lithium metal negative electrode is a key strategy to inhibit lithium dendrites. The coating works through the following mechanisms:

Physical isolation: The dense magnesium hydroxide layer (thickness <500nm) blocks the disordered migration of lithium ions, reduces the local current density difference by 70%, and inhibits dendrite nucleation from the source13;

Chemical purification: Catalytic decomposition of byproducts such as fluoride and sulfide in the electrolyte reduces the frequency of SEI film regeneration by 40% and prolongs the interface stability35;

Mechanical buffering: The compressive strength of the coating reaches 3GPa, which can withstand 300% volume expansion of lithium metal and avoid cracks causing dendrite penetration5.

2. Electrolyte additive revolution: from side reaction inhibition to fast charging performance leap

1. Acidity regulation and side reaction control

As an electrolyte additive, magnesium hydroxide neutralizes free acid (such as HF) with its alkaline properties, stabilizing the pH value of the electrolyte in the optimized range of 6.5-7.0. This effect reduces the electrolyte decomposition rate by 50%, and the battery's cycle capacity retention rate at 4.5V high voltage increases from 65% to 79%39. BYD's actual test shows that adding 0.5% magnesium hydroxide to the electrolyte can reduce the temperature rise of the battery under 1C fast charging by 12°C8.

2. Reconstruction of ion transport channels

Nano-magnesium hydroxide particles (particle size <50nm) form a three-dimensional ion transport network in the electrolyte, increasing the lithium ion migration number from 0.38 to 0.52. This improvement increases the discharge capacity retention rate of the battery at -20°C from 45% to 68%, while supporting 4C fast charging (charging to 80% in 10 minutes)710.

III. Industrialization process: the leap from laboratory to mass-produced vehicles

1. Zehui's technical route has been implemented

The first magnesium hydroxide-based battery pilot production line jointly developed by Zehui and Guoxuan High-tech has achieved the following breakthroughs:

The energy density of the single cell reaches 450Wh/kg, which is 150% higher than the mainstream lithium iron phosphate battery (180Wh/kg);

The cost has dropped by 12%, mainly due to the low raw material cost of magnesium hydroxide (about $200/ton) and the simple coating process15;

The range of mass-produced battery packs has exceeded 800km (NEDC standard), which is 40% higher than the same level of models3.

2. Global Technology Race

Japan: Toyota combines magnesium hydroxide coating with sulfide solid electrolyte to develop a solid-state battery prototype that supports 1,000 km of driving range, and plans to mass-produce it in 20278;

USA: QuantumScape uses a "magnesium hydroxide-carbon nanotube" composite coating to increase the cycle life of lithium metal anodes to 2,000 times, with an energy efficiency of 95%10;

China: CATL's latest patent shows that its magnesium hydroxide-based electrolyte can increase the thermal runaway trigger temperature from 140°C to 180°C, and has passed UL 2580 certification58.

IV. Challenges and the future: from material modification to system integration

Although magnesium hydroxide technology has broad prospects, it still needs to break through three major bottlenecks:

Conductivity optimization: through carbon coating (such as graphene/carbon nanotube composite) or doping with rare earth elements, the ionic conductivity of the coating is increased from 10⁻⁸ S/cm to 10⁻⁴ S/cm310;

Long cycle verification: It is necessary to establish a 10-year (about 3,000 cycles) accelerated aging test system. Currently, only BYD has published 2,000 cycle data (capacity retention rate of 79%)8;

Multi-material synergy: For example, magnesium hydroxide is combined with α-Si3N4 porous membrane to construct a "dendritic physical barrier + chemical passivation" dual protection system. This solution has extended the puncture tolerance time by 6 times in the laboratory59.

Conclusion: The "white revolution" that reshapes the industrial landscape

The dual breakthroughs in magnesium hydroxide technology mark the transition of new energy vehicle power batteries from "gradual improvement" to "disruptive innovation" stage. According to Gaogong Lithium Battery's forecast, by 2028, the global market size of magnesium hydroxide in the field of power batteries will exceed US$5 billion, driving the average range of new energy vehicles to exceed the threshold of 1,000 km. This revolution triggered by basic materials may redefine the competition rules of the global new energy industry - as Zehui's chief engineer said: "Whoever masters the efficient application of magnesium hydroxide will master the lifeline of the next generation of power batteries.