Hexagonal boron nitride (h-BN) is becoming a key material to break through the performance bottleneck in the field of lithium battery heat dissipation. With the rising demand for battery energy density and safety in new energy vehicles and consumer electronics, its unique two-dimensional layered structure, excellent thermal conductivity and electrical insulation properties have shown its revolutionary potential in the field of thermal management.

The thermal conductivity of h-BN (40-300 W/(m-K)) far exceeds that of traditional alumina (30 W/(m-K)) and boehmite (5 W/(m-K)). Research at Tsinghua University has shown that the Coulombic efficiency of h-BN-coated diaphragm is still up to 100% after one hundred cycles, and there is virtually no degradation of discharge capacity. Its layered structure builds a highly efficient thermal conduction channel, which can quickly export the internal heat of the battery. At the same time, the ultra-high resistivity of 10¹³ Ω-cm makes it both electrically insulating, and Jiangsu University has verified that the volume resistivity of its composite phase-change material exceeds 10¹² Ω-cm, which effectively avoids the risk of short-circuit.

With a melting point of nearly 3000°C, h-BN is structurally stable at 400°C. Measurements have shown that batteries containing h-BN coatings did not lose control under thermal shock at 150°C, while the control group caught fire at 120°C. This stability makes it uniquely valuable in scenarios such as high nickel ternary lithium batteries.

Diaphragm coating: After h-BN nanosheets/tubes uniformly cover the diaphragm, the thermal shrinkage rate is less than 5% (30% for traditional diaphragm at 130℃), which significantly inhibits the growth of lithium dendrites.

Composite phase change material: the thermal conductivity of the shaped phase change material with 15% h-BN added reaches 5.2 W/(m-K) (26 times higher than that of pure paraffin), with no leakage at 70℃, solving the hidden problem of mobility.

Thermally conductive interface material: added to gel/adhesive as filler, it can fill the gap between electric core and heat sink, and the interface thermal resistance is significantly reduced in 5G base station applications.

BN(CHINA) Technology reduces the cost of high-purity (99.5%) h-BN powder by 30% through continuous calcination technology, which promotes large-scale application. In terms of process, silane coupling agent modification is used to solve the nano-agglomeration problem, which improves compatibility by 80%; advanced coating machine realizes ±2μm precision control to avoid local overheating. Long-term tests show that the thermal conductivity of the h-BN coating has decreased by only 3% after 500 cycles, while that of the alumina coating has decreased by 25%, thanks to its chemically inert corrosion-resistant properties against the electrolyte.

It is expected that by 2029, the global h-BN heat dissipation material market size will reach 1.2 billion U.S. dollars, lithium battery field share from 15% to 35%. Some car companies have been tried in high-end models, single-vehicle dosage of 0.5-1kg. technical level, h-BN and solid-state electrolyte (such as LLZO) compatibility study has made progress, preliminary data show that the interface impedance reduced by 40%, or pave the way for the commercialization of lithium metal batteries.

As a “thermal conductivity,” h-BN is breaking the traditional material performance boundaries, with the maturity of the preparation technology and cost reduction, is expected to move from the high-end market to the public, to promote the lithium battery energy density and safety of the double enhancement. BN(CHINA) Technology has mass-produced four specifications of products (purity 97%-99.5%), which are widely used in ceramics, coatings, thermal conductive materials and other fields, to further consolidate its leading position in technology.