Biomanufacturing of Hierarchical Biocomposites for High-Performance Thermal Interface Materials - SBIR Topic DPA26TZ03-DV002

Funding Amount:

Est. $1,800,000

Deadline to Apply:

July 22nd, 2026

Objective:

Develop and demonstrate a flexible, polymer-matrix thermal interface material with tunable thermal and mechanical properties, leveraging hierarchical, biocomposite-based microstructures for scalable, sustainable, low-cost thermal management of high-performance electronics and power applications.

Description:

This topic addresses the thermal management challenge of dissipating the large amount of heat generated by today’s high-density microelectronics and power storage systems to ensure and maintain performance, reliability, and safety [3, 4, 6].

Thermal interface materials (TIMs) are a critical component in thermal management. TIMs are designed to fill microgaps and surface irregularities between otherwise bare surfaces of a device and its cooling system. Without a TIM, if two nominally flat and smooth solid surfaces are joined to form a bare contact, surface microroughness can limit the actual area of contact between the two solids to about 1–2% of the apparent contact area [11].

The solid-to-solid conduction through the contact points, along with conduction through the air trapped in noncontact regions, are poor thermal conductors and limit heat transfer from one surface to another. This thermal contact resistance must be reduced by inserting a TIM at the interface to eliminate air voids and fill the gap between the device and cooling system.

The general requirements for a good TIM include:

• Low interfacial thermal resistance

• High thermal conductivity

• Low elastic modulus

• Good adhesion

• Good conformability

• Long-term stability

• Appropriate thermal expansion

This is particularly challenging for mechanically flexible applications because the soft, polymeric materials commonly used as TIM matrices generally have low thermal conductivity (TC) [7, 1], making it difficult to meet thermal management demands.

Drones and electric vehicles present another classic thermal management challenge due to high C-rate battery pack discharge and charge cycles during operation. The drone case may be especially difficult because payload and flight-time constraints often dictate passive thermal management approaches such as heat sinks and air cooling [5], with TIMs serving as a critical component for thermal coupling between the heat sink and battery packaging.

In addition to thermal conductivity demands, power and high-frequency systems often require TIMs that combine high heat conduction with:

• Electrical insulation

• Breakdown resistance

• Low leakage

• Geometric conformity

While traditional thermal pastes and greases perform well under certain conditions, they still face challenges such as insufficient thermal conductivity, aging, and poor reliability when applied in high-frequency, high-power-density applications.

In recent years, significant progress has been made in the design and synthesis of high-performance TIMs. However, balancing interfacial thermal resistance, thermal conductivity, and mechanical properties continues to pose a significant challenge.

Biomanufactured and biocomposite filler-type TIMs with simultaneous high thermal conductivity and electrical insulation [8, 9] may be ideal materials to address these requirements while offering a lower-cost, more sustainable supply-chain solution compared to advanced fillers such as boron-based semiconductors and carbon nanotubes.

PHASE I

This topic is soliciting Direct to Phase II (DP2) proposals only.

The Government expects that the small business has already completed a Phase I-type feasibility effort and developed a prototype TIM that addresses, at a minimum, the basic requirements outlined in the objective above.

For this DP2 STTR, a technical report containing Phase I Feasibility Documentation is required to demonstrate that Phase I feasibility has been met. The documentation must contain a detailed description of the technical plan, milestones, and supporting data demonstrating that the proposed technology satisfies the Phase I deliverables and is at an appropriate maturity level for Direct to Phase II funding.

The proposer must substantiate that Phase I-equivalent feasibility has been achieved outside of the SBIR/STTR program.

PHASE II

The Direct to Phase II effort will focus on developing, integrating, and demonstrating a scalable biocomposite thermal interface material capable of balancing high thermal conductivity, electrical insulation, and mechanical flexibility.

Candidate TIMs must demonstrate scalable (bio)manufacturing and structural control of biocomposite filler architectures. The proposed materials must achieve thermal conductivity exceeding current state-of-the-art boron nitride-based soft polymer composite TIMs, specifically greater than 23 W/m-K through-plane thermal conductivity.

The effort should include modeling of processing-structure-property relationships to enable optimization of thermal conductivity while maintaining flexibility. Mechanical properties must be tunable while preserving thermal performance and electrical insulation.

Candidate biocomposite TIMs must demonstrate:

• Tailorable thermal conductivity across an achievable performance range

• Tunable flexibility versus thermal conductivity

• Stable thermal conductivity after 1,000 bending cycles at 100% maximum strain

• Sufficient adhesion, such as performance measured through a 90° peel test

• Modulus and flexibility comparable to common elastomers

Demonstration testing must be conducted using a prototype system operating in a realistic environment. Suitable demonstration platforms include passively cooled lithium-ion battery packs used in FPV drones or electric vehicles operating under high C-rates, as well as state-of-the-art CPUs and GPUs operating at maximum thermal design power (TDP).

Thermal performance will be compared against conventional TIM solutions, including thermal pastes containing metal or metal oxide fillers, phase-change materials, and alumina-based thermal pads.

The objective is to demonstrate that the biocomposite TIM successfully manages thermal loads in conditions where conventional TIMs fail. Examples include maintaining battery pack temperatures at or below 35°C regardless of discharge rate and ambient conditions, or maintaining CPUs and GPUs below maximum junction temperature during peak operation. The biocomposite TIM must provide a statistically significant reduction in device temperature compared to standard TIM technologies.

In addition to technical development, the project must include commercialization and transition planning. Throughout the effort, proposers are expected to engage both commercial and military stakeholders to refine operational requirements and deployment scenarios. Manufacturing scale-up plans and a technoeconomic analysis (TEA) must also be developed.

The final report must include technology transfer documentation identifying pathways for both commercial and military adoption.

Base Milestones

Month 1: Identify candidate TIM compositions, biocomposite designs, processing methods, and a design-of-experiments approach for optimization. Establish target performance metrics.

Month 3: Complete initial processing-structure-property modeling, provide preliminary TEA results, and downselect to final TIM candidates.

Month 6: Conduct initial thermal management testing in real-world systems and validate modeling results.

Month 9: Quantify thermal and mechanical performance, compare results against state-of-the-art alternatives, and provide initial long-term stability data.

Month 12: Demonstrate prototype TIM performance in an operational environment.

Base Deliverables

Month 1: TIM candidate selection and design-of-experiments report.

Month 3: Modeling results and technoeconomic analysis report.

Month 6: Thermal management performance report and model validation results.

Month 9: Laboratory prototype demonstration and report documenting thermal, mechanical, and stability performance.

Month 12: Final Phase II report documenting the prototype TIM composition, microstructural design, materials processing and scale-up approach, thermal and stability performance, operational testing results, validated models, TEA findings, and commercialization and transition plans.

Option Milestones

Month 15: Scale manufacturing to pilot plant quantities.

Month 18: Integrate the high-thermal-conductivity TIM into a battery thermal management system.

Option Deliverables

Month 15: Delivery of 20 grams of high-TC biocomposite TIM and a report documenting pilot plant design, operations, and batch-to-batch consistency in thermal and mechanical performance.

Month 18: Report detailing battery thermal management system integration and resulting performance improvements.

PHASE III DUAL USE APPLICATIONS

Successful development of a biomanufactured, high-thermal-conductivity biocomposite TIM could support a broad range of military and commercial applications.

Potential Department of Defense applications include military FPV drones, soldier-worn power systems, ground vehicle power electronics, and directed-energy thermal management systems.

Potential commercial applications include delivery drones, electric vehicle battery packs, data center CPUs and GPUs, and LED lighting systems.

Who will win?

If you can achieve the objective above better than any other company on the market, you have a very high-likelihood of success and should apply.

Who is eligible to apply?

Any company that meets the following criteria:

• For-profit company

• U.S.-owned and controlled.

• 500 or fewer employees (including affiliates)

How Can BW&CO Help?

1) End-to-end support including, strategy, writing of the full proposal, and administrative & compliance support.

2) Proposal strategy and review.

3) Administrative & compliance support.

Request to talk with a member of our team by completing the form below: