Against the backdrop of smartphones exceeding 7500mAh daily power consumption and 5G devices witnessing a 30% surge in energy demand, power banks-the "secondary power cores" of mobile energy-are undergoing a transformative leap from liquid to solid-state battery technologies. From the 100-cycle lifespan of early nickel-cadmium batteries to the current milestone of solid-state batteries surpassing 1000 cycles, energy density, safety, and lifespan are being redefined in the power bank sector.
I. The Liquid-State Era: A Dual Dominance of Lithium-Ion and Polymer Batteries
The current power bank market remains predominantly liquid-electrolyte-based, with lithium-ion (Li-ion) and lithium-polymer (LiPo) batteries accounting for over 98% of market share.
Lithium-Ion Batteries: Balancing Energy Density and Cost
Represented by cylindrical 18650 cells, lithium-ion batteries are the mainstream choice for high-capacity power banks. Xiaomi's 165W fast-charging power bank employs four 18650 cells in parallel, achieving a 10000mAh capacity and 165W output power. Its core strength lies in a volumetric energy density of 250Wh/L-three times higher than nickel-metal hydride batteries. However, the flammability of liquid electrolytes necessitates stringent overcharge protection, such as the HAT2027 chip's triple-stage safeguards, resulting in a 15–20% cost premium over polymer batteries.
Lithium-Polymer Batteries: A Safety Revolution Through Flexible Design
Leveraging gel electrolytes and pouch-type packaging, lithium-polymer batteries enable thickness customization from 0.5mm to 10mm. Huawei's 66W SuperCharge power bank adopts polymer stacking technology, reducing weight by 23% compared to 18650-based designs while maintaining a 12000mAh capacity. Its safety credentials include operational stability from -20°C to 60°C and a "zero-ignition" record in puncture tests. However, polymer cells typically exhibit a 500-cycle lifespan-20% shorter than 18650 cells-and experience capacity decay during high-current discharge.
II. The Solid-State Revolution: Kuxiu S2 Leads Technological Breakthroughs
The May 2025 launch of the Kuxiu S2 magnetic wireless power bank marked the first mass-market application of solid-state batteries. Equipped with a 5000mAh solid-state cell, this device achieves three milestones by replacing traditional organic electrolytes with sulfide-based solid electrolytes:
Thermal Runaway Threshold Increased by 400%
In Florida's high-temperature tests, the Kuxiu S2 sustained iPhone 16 Pro Max charging for six consecutive days, maintaining surface temperatures below 45°C-28°C cooler than liquid-battery counterparts. Its solid electrolyte boasts an 800°C melting point, dwarfing the 150°C flammability threshold oliquid electrolytes.
Cycle Lifespan Exceeds 1000 Cycles
Lab data reveals 92% capacity retention after 1000 cycles at a 1C charge/discharge rate, compared to 80% capacity decay in 18650 cells under identical conditions.
Fast-Charging Compatibility Revolution
By incorporating LiNbO₃-coated cathodes, the Kuxiu S2 achieves 93% energy conversion efficiency in 15W wireless fast-charging mode-an 8-percentage-point improvement over liquid batteries. Its 20W wired fast-charging fully replenishes an iPhone in 1.5 hours, 35% faster than conventional solutions.
III. The Battle of Technological Pathways: The Eternal Trade-off Between Cost and Performance
The power bank battery landscape now reflects a "liquid-dominant, solid-state-penetrating" dynamic, with technological choices revolving around three core contradictions:
Energy Density vs. Safety
NMC (LiNiₓCoᵧMn₁₋ₓ₋ᵧO₂) lithium-ion batteries offer 300Wh/kg energy density but a 150°C thermal runaway threshold, while LFP (lithium iron phosphate) batteries prioritize safety at 180Wh/kg. Solid-state batteries, leveraging lithium metal anodes, theoretically exceed 500Wh/kg but face challenges with lithium dendrite growth.
Cost vs. Lifespan
18650 cells cost approximately 2perunitwithan800−cyclelifespan,whilepolymercellsfetch3.5 per unit for 500 cycles. Solid-state cells, initially priced at 8perunit,areprojectedtodropto4/Wh by 2027 as production scales at CATL and Samsung SDI.
Fast-Charging Demand vs. Thermal Management
20W+ fast-charging requires cell internal resistance below 5mΩ, necessitating liquid cooling in liquid batteries. Solid-state batteries, with higher ionic conductivity, enable air cooling. The Romoss 65W fast-charging power bank employs dual solid-state cells in parallel, achieving a 20000mAh capacity in 30% less volume than liquid-based designs.
IV. Industrial Ecosystem: A Full-Chain Transformation from Materials to End Products
Battery advancements are reshaping the entire power bank value chain:
1. Upstream Materials
Electrolytes: Capchem's solid-state electrolyte additives reduce interfacial impedance by 40%.
Cathodes: Easpring's LiNi₀.₈Co₀.₁Mn₀.₁O₂ high-nickel material achieves 1500+ cycles.
Anodes: BTR's silicon-carbon composites deliver 1500mAh/g specific capacity.
2. Midstream Manufacturing
Packaging: ATL's pouch-cell yields reach 98%, 12 percentage points higher than cylindrical cells.
Testing: Star Cloud's solid-state battery nail-penetration tester simulates 10m/s puncture speeds.
3. Downstream Applications
Consumer: Anker 737 PowerBank supports 65W bidirectional charging.
Industrial: DJI's drone-specific power banks integrate temperature sensors for -30°C to 70°C operation.
Medical: Mindray's customized power banks feature dual-circuit protection and IEC 60601 compliance.
V. Future Outlook: 2030 Roadmap and Market Forecasts
According to China Research and Intelligence (CRI), by 2030:
Solid-state batteries will capture 35% of the premium power bank market.
Lithium-sulfur batteries (500Wh/kg energy density) are poised for limited commercialization.
Magnesium-ion batteries ($0.1/Wh cost) will enter laboratory validation phases.
Geographically, the North American shared power bank market will shift toward Asia-Pacific, with Chinese brands leveraging technological innovation and cost control to secure over 60% global market share. Companies like Xiaomi and Huawei are pioneering "power bank + IoT" ecosystems, enabling smart power allocation via built-in Bluetooth chips.
As power banks evolve from "emergency tools" to "mobile energy hubs," each battery breakthrough redefines the boundaries of mobile life. The leap from liquid to solid-state batteries transcends materials science-it embodies humanity's relentless quest for energy mastery. In this battle between range and safety, the first to conquer the "impossible triangle" of energy density, safety, and cost will dominate the next decade of mobile energy.