26650 4000mAh High Capacity LFP Battery

$37.00

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Commercial-grade 26650 LiFePO₄ cell, 4000mAh nominal capacity, 3.2V, 142Wh/kg energy density, 2000 cycles at 100% DOD. Order now.

Description

4000mAh High-Capacity 26650 Lithium Iron Phosphate (LFP) Cylindrical Battery | ATOMFAIR

COMMERCIAL GRADE · PRODUCTION

Product Overview

The ATOMFAIR® 26650 High-Capacity LFP (LiFePO4) cylindrical cell delivers industry-leading energy density of 142Wh/kg with a nominal capacity of 4000mAh, making it one of the highest capacity 26650 LFP cells available on the market. Engineered for long-duration and high-voltage series configurations, this cell offers exceptional cell-to-cell consistency, a design life of 20 years, and a 5-year warranty. With 1C charge/discharge cycle life reaching 6000 cycles and standard cycle life of 2000 cycles at 100% DOD, it provides outstanding longevity for stationary storage, EV auxiliary batteries, and backup power systems. Featuring a built-in safety vent and nail penetration without fire or explosion, it combines high energy with intrinsic LFP safety. For bulk inquiries or official volume quotations, please contact us via email at inquiry@atomfair.com.

Technical Specifications

PARAMETER VALUE
General Parameters
Nominal Capacity (0.2C) 4000 mAh
Minimum Capacity (0.2C) 4000 mAh
Nominal Voltage 3.2 V
Energy Density 142 Wh/kg
Internal Resistance ≤20 mΩ
Weight ≈90 g
Cycle Life (100% DOD, 25°C) 2000 cycles
Charge Parameters
Max. Charge Voltage 3.65 ± 0.03 V
Standard Charge Current 0.5C
Max. Charge Current 2C
Discharge Parameters
Min. Discharge Voltage 2.0 V
Standard Discharge Current 1C
Max. Continuous Discharge Current 3C
Temperature Ranges
Charge Temperature 0°C to 45°C
Discharge Temperature -20°C to 60°C
Manufacturing Compliance: Fully traceable production under ISO 9001:2025 and IATF 16949 standards. Custom form factors or electrode formulations available upon request.

Key Features & Advantages

  • Highest Capacity 26650 LFP Cell: 4000mAh nominal capacity with 142Wh/kg energy density — ideal for high-voltage, large-format battery packs.
  • Exceptional Cycle Life: 6000 cycles at 1C charge/discharge, and 2000 cycles at 100% DOD under standard conditions.
  • Long Design Life & Warranty: 20-year design life with 5-year warranty, ensuring reliable performance for long-term installations.
  • Excellent Cell Consistency: Suitable for high-voltage series configurations with minimal voltage variation between cells.
  • Intrinsic Safety: Built-in explosion-proof vent, passes nail penetration without fire or explosion, zero thermal runaway risk.

APPLICATION SCOPE: Stationary energy storage systems (ESS), EV auxiliary batteries, telecom backup, UPS systems, solar street lights, and high-voltage battery packs requiring excellent cell matching.
PACKAGING: Anti-static plastic trays (50 cells per tray, 200 cells per master carton). Insulated terminal covers included for safe transport.
IMPORTANT NOTICE: For maximum cycle life, operate cells within recommended voltage window (2.5V – 3.65V) and avoid sustained high-temperature operation. Always use a dedicated LFP BMS with cell balancing, especially for high-voltage series strings.

TAILORED SOLUTIONS FOR RESEARCH
Contact our engineering team for technical support or official institutional quotations.
EMAIL: inquiry@atomfair.com
Manufacturer: Atomfair LLC
Brand: ATOMFAIR®

This lithium iron phosphate cell must be stored in a dry environment away from conductive materials. The integrated safety vent must remain unobstructed during use to ensure proper pressure relief.

  • Safety Vent Constraint: The cell contains a safety vent designed to release internal pressure under fault conditions and must not be blocked or punctured.

Follow these steps to safely handle and initialize the cell for first use. Proper precautions prevent damage and ensure reliable performance.

Required Equipment: Digital multimeter

  1. Inspect Cell
    Inspect the cell casing for any physical damage, dents, or leaks before handling.
  2. Measure Voltage
    Measure the open-circuit voltage using a digital multimeter to confirm the cell is not shorted or deeply discharged.
  3. Connect to Charger
    Connect the cell to a compatible LFP charger set to the appropriate constant current and constant voltage limits.

How does the 4000mAh 26650 LFP cell's cycle life at 1C charge/discharge compare to its standard 100% DOD cycle life, and what trade-off does this represent for high-rate applications?

The ATOMFAIR 26650 LFP cell delivers 6000 cycles at 1C charge/discharge, significantly exceeding the 2000 cycles at 100% DOD under standard conditions. This trade-off means that operating at a consistent 1C rate yields three times the cycle life, making it ideal for high-rate stationary storage or backup power systems where deep discharges are avoided, but full DOD cycling may be preferred for applications requiring maximum energy utilization per cycle.

Can the ATOMFAIR 26650 LFP cell be integrated into existing 12V or 24V battery packs designed for other 26650 chemistries, and what voltage constraints must be considered?

Yes, the cell's nominal voltage of 3.2V and maximum charge voltage of 3.65±0.03V are standard for LFP chemistry, allowing direct integration into packs designed for LFP-based 26650 cells. However, compatibility with packs originally designed for higher-voltage chemistries like NMC or LCO requires careful BMS reconfiguration to respect the 2.0V minimum discharge voltage and avoid over-discharge, as the lower voltage plateau may trigger premature cutoff in systems calibrated for 3.6V nominal cells.

What are the critical handling and storage requirements for the ATOMFAIR 26650 LFP cell to ensure safety and prevent capacity degradation?

The cell must be charged only within 0°C to 45°C and discharged within -20°C to 60°C to avoid irreversible capacity loss or internal damage. Storage at partial charge (around 30-50% SOC) in a dry, cool environment below 25°C is recommended to minimize calendar aging. The built-in safety vent provides passive overpressure protection, but mechanical abuse such as crushing or puncturing should be avoided despite nail penetration testing showing no fire or explosion.

The ATOMFAIR 26650 LFP cell delivers 4000mAh capacity with 142Wh/kg energy density and exceptional cycle life of 6000 cycles at 1C rate, yet its charge temperature window of 0–45°C and reduced 2000-cycle life at 100% DOD are critical operational constraints for pack designers.

Positive

  • Highest capacity in 26650 LFP format: With 4000mAh nominal capacity and 142Wh/kg energy density, this cell sets a benchmark for 26650 lithium iron phosphate batteries, enabling high-energy-density packs for stationary storage and auxiliary power.
  • Inherent safety and long cycle life: The LFP chemistry passes nail penetration without fire or explosion, and the cell supports 6000 cycles at 1C charge/discharge, offering both intrinsic safety and exceptional longevity under moderate use.

Trade-offs

  • Narrow charge temperature range: Charging is only permitted between 0°C and 45°C; operation outside this window risks lithium plating and capacity fade, requiring thermal management in cold or hot environments.
  • Reduced life at full depth of discharge: Standard cycle life at 100% DOD is 2000 cycles—one third of the 6000 cycles achievable at 1C charge/discharge—meaning full-capacity cycling significantly shortens service life.

Every advanced material, component, equipment, and instrument in our catalog is backed by rigorous testing. We maintain strict internal quality management frameworks and align with CE conformity metrics to deliver transparent, reproducible performance data via our public open-science repository.

To request raw batch performance data, submit formal vendor registration paperwork, or execute a fast-turnaround R&D manufacturing loop, contact us at inquiry@atomfair.com.

Item is dispatched under the Atomfair Shipping & Delivery Framework (Free worldwide shipping on orders over $59 USD). Return is governed by the Atomfair Return & Refund Policy (7-day technical return window).