EV & Energy Storage
Thermal Interface Materials for EV Battery Packs, Power Electronics & ESS
Sheen provides thermal pads, silicone-free pads, disposable thermal gels, phase change materials, and sealing foams
for battery packs, BDU/BMS, OBC/DC-DC, inverters, motor controllers, and energy storage systems—engineered for insulation,
low assembly stress, manufacturability, and long-term reliability.
Thermal challenges
System map
Solutions by subsystem
Selection matrix
Reference cases
Validation & QA
RFQ checklist
Typical deliverables: die-cut parts, sheets/rolls, PI/fiberglass carriers, single/double-sided tack, cartridges for automated dispensing.
What EV & ESS designers optimize for
Safety + insulation
High dielectric strength and stable insulation across temperature cycling; controlled thermal impedance to reduce hotspots.
Dielectric strength
UL94 V-0 options
Low thermal resistance
Assembly stress control
Gap tolerance, compressibility, and low rebound stress to protect solder joints, power modules, and fragile packages.
Compressibility
Low stress
Gap tolerance
Reliability in harsh environments
Thermal shock, humidity, high-temperature aging, and vibration—materials must stay stable over long service cycles.
Thermal cycling
Humidity
Automotive-grade workflow
Thermal pads (example range)
Silicone-free pads (example range)
Disposable thermal gels
Phase change activation
System map: where TIMs are applied
Use this map to align your thermal interface choice with subsystem heat density, assembly constraints and contamination sensitivity.
EV (vehicle side)
- cell-to-cold-plate, module-to-frame, pack-to-baseplate, thermal runaway isolation zones
- contactor/relay heat paths, PCB-to-housing gaps, silicone migration-sensitive zones
- transformer/MOSFET heat transfer, complex height variation, automated dispensing
- power module interface, low bondline & high reliability
- ECU hotspot control, radar module thermal + EMI composite needs
ESS (stationary storage)
- IGBT/MOSFET module interface, heat spread to cold plate / heat sink
- module-to-tray gaps, pack sealing & vibration damping
- power stage interfaces, enclosure-to-base heat path
- UPS, control boards, relays, busbar junction areas
Solutions by subsystem
Below are typical subsystem-level selections.
Different project solutions require different model selections. Please consult our engineers to determine the appropriate product model.
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Recommended Silicone-free thermal pads (AF series) for silicone-sensitive assemblies; Silicone pads (SF) where maximum conductivity/temperature range is needed.
- : silicone-free pads reduce risk of low-molecular siloxane migration.
- : select Shore 00 class matched to clamp load to avoid warpage and stress transfer.
Recommended Thermal gels (SE series, 2.0–10.0 W/m·K) for controlled dispensing; pair with pads for hybrid interfaces.
- : compatible with dispensing, screen printing or doctor-blade coating (automation-friendly).
- : gels improve wetting on micro-rough surfaces and reduce interface thermal resistance.
Recommended Phase change materials for heat sink/cold plate interfaces (≈50–52°C activation), or high-k pads where thicker gaps exist.
- : low thermal resistance after phase transition; natural tack simplifies handling.
- : gap tolerance for tolerance stack-ups; optional carriers (PI/fiberglass) improve handling.
Typical needs: compressible gap filling, insulation, stable performance through thermal cycling.
Recommended Silicone thermal pads (SF series) for module-to-plate gaps; sealing/foam silicone for support, dust/moisture sealing and vibration damping.
- When gaps vary: choose thicker pads (0.5–5.0mm class) or gels for complex height differences.
- When insulation is critical: prioritize models with higher dielectric strength and UL94 V-0 options.
- Manufacturing: die-cut parts to prevent overhang and improve assembly repeatability.
Typical needs: PCB-to-housing gaps, contamination-sensitive components, long-term stability.
Recommended： Silicone-free thermal pads (AF series) for silicone-sensitive assemblies; Silicone pads (SF) where maximum conductivity/temperature range is needed.
- Contamination-sensitive zones: silicone-free pads reduce the risk of low-molecular siloxane migration.
- Assembly: select the Shore 00 class matched to the clamp load to avoid warpage and stress transfer.
Typical needs: fill complex gaps, control thickness/shape, support automation.
Recommended： Thermal gels (SE series, 2.0–10.0 W/m·K) for controlled dispensing; pair with pads for hybrid interfaces.
- Process: compatible with dispensing, screen printing, or doctor-blade coating (automation-friendly).
- Design intent: gels improve wetting on micro-rough surfaces and reduce interface thermal resistance.
Typical needs: high heat flux, stable impedance, fast assembly and rework strategy.
Recommended： Phase change materials for heat sink/cold plate interfaces (≈50–52°C activation), or high-k pads where thicker gaps exist.
- PCM advantage: low thermal resistance after phase transition; natural tack simplifies handling.
- Pad advantage: gap tolerance for tolerance stack-ups; optional carriers (PI/fiberglass) improve handling.
Typical needs: localized hotspots, lightweight packaging, stable long-term adhesion/fit.
Recommended： Pads (SF) for ECU/cockpit modules; gels for radar modules and height differences; consider EMI + thermal co-design where required.
- Radar: prioritize controlled wetting, low stress, and stable performance at elevated ambient temperatures.
- Cockpit: focus on space optimization and stable thermal performance under constrained airflow.
Typical needs: reliability in thermal cycling/humidity; stable insulation and repeatable assembly.
Recommended： Pads and PCMs for module-to-cold-plate interfaces; gels for complex gaps; sealing foams for enclosure integrity.
- PV / wind/converter cabinets: focus on stable impedance through temperature cycles and robust manufacturing flow.
- Stationary racks: include sealing/damping material to reduce vibration damage and prevent dust/moisture ingress.
Recommended Pads (SF) for ECU/cockpit modules; gels for radar modules and height differences; consider EMI + thermal co-design where required.
- : prioritize controlled wetting, low stress, and stable performance at elevated ambient temperatures.
- : focus on space optimization and stable thermal performance under constrained airflow.
Recommended Pads and PCMs for module-to-cold-plate interfaces; gels for complex gaps; sealing foams for enclosure integrity.
- : focus on stable impedance through temperature cycles and robust manufacturing flow.
- : include sealing/damping material to reduce vibration damage and prevent dust/moisture ingress.
Product selection matrix (typical ranges & example SKUs)
This matrix is designed for fast engineering selection and procurement comparison. Confirm the final SKU after gap + clamp-load verification.
| Material family | Best-fit use cases | Typical thermal conductivity | Thickness / process | Thickness/process | Example SKUs |
|---|---|---|---|---|---|
| Silicone Thermal Pad (SF) | Battery modules, ECU, and power electronics where gap tolerance matters | 1.5–15.0 W/m·K | 0.3–10.0 mm; sheets & die-cut parts | UL94 V-0 options; dielectric strength often >6 / >8 kV/mm; wide temp range (model-dependent) | SF600 / SF600D / SF800 / SF1000 |
| Silicone-Free Pad (AF) | BDU/BMS and contamination-sensitive zones | 1.0–6.0 W/m·K | 0.5–5.0 mm; sheets & die-cut parts | Compression/elongation guidance supports clamp-load design; reduces silicone migration concerns | AF300 / AF500 / AF600 |
| Thermal Gel (SE) | OBC/DC-DC, radar modules, complex height differences | 2.0–10.0 W/m·K | Dispensable; supports automation | Compression/elongation guidance supports clamp-load design; reduce silicone migration concerns | SE20 / SE40 / SE80 / SE100 |
| Phase Change Material | Inverter/PCS heat sink or cold-plate interfaces | — (focus on low interface resistance) | Disposable; supports automation | Phase transition around 50–52°C; natural tack; suitable for high-efficiency processor/power interfaces | PCM series (custom cut) |
| Foam Silicone | Battery pack sealing, support, damping, dust/moisture barrier | — | Seals / gaskets / cushioning parts | Closed-cell; high compressibility & resilience; supports pack-level mechanical protection | Foam silicone variants |
Need a fast match? Send your gap profile, clamp load, dielectric requirement, and operating temperature window.
Reference designs & case snapshots
These are common, repeatable architectures you can reference during early-stage selection and RFQ alignment.
BMS thermal interface
Pad-based heat path from hotspot components to shield/cover. Low stress and stable insulation under cycling.
Example: SF600D
BMS
OBC thermal architecture
Hybrid approach: gel for complex gaps + pad for defined interfaces. Supports automated dispensing and repeatability.
Example: SE20 + SF500
OBC
ECU / controller hotspots
Pad interface to spread heat to the enclosure/heat sink with controlled compression to avoid board warpage.
Example: SF500 / SF500-PI
ECU
Radar module (thermal + packaging)
Gel-based interface improves wetting and controls stress; supports mixed thermal/EMI co-design where required.
Example: SE40
77G radar
EOP controller interface
Dispensable gel fills irregular gaps and maintains interface contact under vibration and temperature variation.
Example: SE30
EOP
Pack sealing & damping
Closed-cell foam silicone for support + sealing, helping reduce dust/moisture ingress and mechanical shock impact.
Foam silicone
Pack level
Validation & quality (what we verify)
Thermal performance verification
- Thermal conductivity & thermal resistance characterization
- Interface stability through pressure/temperature variation
- Wetting and contact quality for gels and PCMs
Reliability screening
- Thermal shock/temperature cycling
- Humidity aging / high-temperature aging
- Process stability for dispensing / die-cut manufacturing
RFQ checklist (send this to get a fast, accurate recommendation)
Engineering inputs
- Subsystem: Battery / BMS / BDU / OBC / DC-DC / Inverter / ECU / PCS
- Gap profile (min/max), target bondline thickness, clamp load
- Dielectric requirement, UL94 target (if required), operating temperature
- Contamination sensitivity (silicone-free needed?)
Procurement inputs
- Annual volume / pilot volume, expected lead time, incoterms
- Preferred format: sheet / roll / die-cut / cartridge
- Required documentation: RoHS/REACH (if applicable), inspection plan
- Sample plan: prototype → EVT/DVT/PVT
Tip: If you provide a simple “component list + gap + clamp load”, we can shortlist 2–3 material families (pad vs silicone-free vs gel vs PCM) for quick comparison.