[SMM Analysis] Are There Other "Alternatives" for Hard Carbon Raw Materials as the Import Price of Coconut Shell Charcoal Continues to Rise?

SMM News on June 20:

According to the latest data from the General Administration of Customs, China imported 11,622.7 mt of husk charcoal in May 2025, down 15% MoM and 21% YoY. The average import price of husk charcoal in May was $593.18/mt. In March, the average import price was $549.46/mt, indicating a MoM increase in the average import price per mt of husk charcoal.

In the face of rising import prices for coconut shell charcoal (due to tight raw material supply caused by disasters in Southeast Asia in 2024 and sustained increases in import prices in 2025), diversified technological pathways have emerged for "alternative" materials to sodium-ion battery hard carbon anodes, mainly falling into the following three categories:

1. Biomass-based alternatives: Low cost, high supply potential

Straw-based hard carbon

China's annual straw production exceeds 1 billion mt (2023 data for China), with a cost of only 300-600 yuan/mt, a carbon yield of approximately 20%, and a per-mt cost that is only 1/10th that of coconut shell charcoal. Theoretically, it can support 8 TWh of sodium-ion battery demand.

Through optimization of fluidized bed technology, the capacity per gram of straw-based hard carbon reaches 280-300 mAh/g, approaching that of coconut shell-based hard carbon (300 mAh/g).

Bamboo-based hard carbon

China produces 4.5 million mt of medium-diameter bamboo annually, with bamboo-based charcoal costs ranging from 500-1,000 yuan/mt. Its performance is close to that of coconut shell charcoal (energy density of 28 Wh/kg vs. 28.11 Wh/kg for coconut shell), and bamboo has high hardness and uniform structure, resulting in more stable pores after carbonisation.

In 2025, bamboo-based hard carbon has undergone batch testing, meeting the demands of applications such as two-wheelers and energy storage systems (ESS).

Sugar/starch-based hard carbon

Glucose and starch are hydrothermally carbonized, with particle size controlled through additive formulations.

The raw material sources are broad (corn, sweet potatoes, etc.), with better consistency than coconut shell (fewer impurities). The capacity per gram exceeds 300 mAh/g, making it suitable for high-end batteries.

It requires a purification process, with costs slightly higher than those of straw-based hard carbon (approximately 800-1,200 yuan/mt), but the supply chain is autonomous and controllable.

2. Resin-based hard carbon: High performance, high cost, suitable for high-end applications

Technological advantages: The uniformity of pore structure in phenolic resin-based hard carbon is improved by 30%, with excellent anti-swelling performance, a capacity per gram of 350 mAh/g (superior to coconut shell), and a high retention rate after 10,000 cycles.

The price of resin raw materials is 3-5 times that of coconut shell, with a carbon yield of only 20%-35%. The current price is over 50,000 yuan/mt.

3. Pitch-based hard carbon: Ultra-low cost, performance to be optimized

A byproduct of petroleum/coal tar pitch, with costs of only 2,000-3,000 yuan/mt and a carbon yield of 54% (far exceeding that of biomass).

The front-end impurity removal cost is high, and it is prone to graphitisation at high temperatures (due to insufficient interlayer spacing), with low initial coulombic efficiency, requiring pre-oxidation and cross-linking modification.

Application Scenarios: Low-end energy storage systems (ESS) and low-speed vehicles, with prices potentially dropping to 20,000-30,000 yuan/mt.

IV. Short-term and Long-term Substitution Strategies

In the short term, focus on biomass-based materials, prioritizing bamboo-based and straw-based materials (due to their low cost and sufficient supply), complemented by some resin-based materials (to enhance the performance of high-end batteries). In the long term, scale up pitch-based materials (after the modification technology matures) + sugar-based/starch-based materials (due to their consistency advantages), aiming to reduce the target cost to a level comparable to that of graphite anodes (30,000-50,000 yuan/mt). Achieve diversified "cost-effective substitutions."

The "cost-effective substitution" of coconut shell charcoal is not a single solution but a diversified matrix of "biomass-based materials as the mainstay, supplemented by resin/pitch-based materials":

Biomass materials such as straw and bamboo-based materials have become the current mainstream choices due to their cost advantages (<1,000 yuan/mt) and supply advantages (100-million-mt scale);

Resin-based materials meet the demand for high-end performance, while pitch-based materials target the ultra-low-cost market. Technological iterations continuously expand the boundaries of raw materials, driving the transition of sodium-ion battery hard carbon from "reliance on imports" to "self-sufficiency and controllability."

SMM New Energy Research Team

Wang Cong 021-51666838

Ma Rui 021-51595780

Feng Disheng 021-51666714

Lv Yanlin 021-20707875