Thermal management plays a critical role in preventing dendrite formation in lithium-based batteries, directly influencing cycle life, safety, and performance. Dendrites, needle-like metallic growths that form on anode surfaces during charging, can pierce separators, cause internal short circuits, and lead to thermal runaway. Maintaining optimal temperature ranges ensures homogeneous lithium plating and stripping, suppressing uneven deposition that initiates dendrite nucleation.

The ideal temperature window for stable lithium plating falls between 20°C and 60°C. Below 20°C, lithium ion mobility decreases, increasing overpotential and promoting dendritic growth due to sluggish kinetics. Above 60°C, accelerated side reactions between electrolytes and electrodes degrade interfaces, exacerbating inhomogeneous plating. Studies demonstrate that cells cycled at 25°C exhibit 80% fewer dendrites compared to those at 0°C, while temperatures above 60°C reduce cycle life by over 50% due to electrolyte decomposition.

Heating and cooling systems must maintain this narrow operational range. Positive temperature coefficient (PTC) materials are widely used for heating, self-regulating resistive heat output to prevent localized overheating. Thin-film PTC heaters integrated into battery packs can uniformly elevate cell temperatures from subzero conditions to 25°C within 5 minutes, reducing early-stage dendrite formation during cold starts. For cooling, microfluidic channels embedded in battery modules dissipate heat efficiently. Liquid-cooled systems with 0.5 mm wide channels reduce peak temperatures by 15°C compared to passive cooling, maintaining surface temperatures below 40°C even at 3C discharge rates.

Integration with battery management systems (BMS) enables real-time thermal regulation. Advanced BMS algorithms adjust heating and cooling outputs based on temperature sensors distributed across cells. Predictive models use impedance data to preemptively activate thermal controls before dendrite-promoting conditions arise. Systems combining PTC heaters and microfluidic cooling report 30% longer cycle life in NMC-graphite cells by keeping temperatures within ±2°C of the 30°C setpoint.

Cycle life improvements under thermal control are significant. Lithium-metal cells with active temperature management achieve over 500 cycles at 90% capacity retention, whereas uncontrolled cells degrade below 80% within 200 cycles. In graphite anodes, maintaining 35°C during fast charging at 2C rates reduces lithium plating by 70%, extending life by 400 cycles. Data from pouch cells show that every 10°C reduction in temperature variation across a module improves longevity by 15%.

Material selection further enhances thermal systems. Phase-change materials (PCMs) with melting points near 30°C buffer against transient spikes, while thermally conductive fillers like boron nitride in separators improve heat distribution. Solid-state batteries benefit from ceramic electrolytes with high thermal stability, allowing operation up to 80°C without dendrite acceleration.

The interplay between thermal gradients and plating uniformity is well-documented. Infrared imaging reveals that regions just 5°C cooler than adjacent areas attract preferential lithium deposition, initiating dendrites. Active thermal homogenization mitigates this; systems with distributed heating reduce spatial temperature differences to under 1°C, eliminating localized plating hotspots.

Future developments focus on adaptive thermal control. Machine learning models trained on degradation data optimize temperature setpoints dynamically, while self-healing electrolytes combined with thermal management further suppress dendrites. The synergy of precise heating, cooling, and BMS integration remains essential for next-generation batteries.

In summary, thermal management is indispensable for dendrite prevention. Regulating temperatures between 20–60°C via PTC heaters, microfluidic cooling, and BMS coordination ensures homogeneous plating, improves cycle life by over 30%, and enhances safety. Continued advances in materials and adaptive control will further solidify its role in battery technology.