266J9 Laptop Battery Compatible with Dell Inspiron 5490 - Replacement

Our review of the 266J9 Laptop Battery finds it best suited for Dell users who need a straightforward, OEM-compatible replacement with clear safety certification. The battery replaces several Dell part numbers including 266J9, MV07R and others, and its main appeal is a direct fit and familiar 11.4V, 51Wh specification that matches the original smaller 3-cell packs found in many Inspiron and G series notebooks. This review focuses on real-world fit, advertised capacity, and the practical tradeoffs between the 51Wh 3-cell option and larger 68Wh 4-cell alternatives.

Key Features

• Compatible part numbers: Covers multiple Dell part numbers so buyers can match the exact replacement and reduce the risk of ordering the wrong pack.
• Battery chemistry: Uses Li-ion chemistry for typical laptop performance and consistent voltage output under normal loads.
• Voltage and capacity: Provides 11.4V and a rated 51Wh (4255mAh) capacity, offering the same nominal power as many original 3-cell packs.
• Certifications: CE and FCC certification indicate the pack meets common safety and electromagnetic standards for consumer electronics.
• Warranty support: Includes a 30 day refund window and 12 month replacement, which helps mitigate early failure concerns.
• Direct replacement fit: Intended for Inspiron 5490 and selected G3/G5 series models for an easy swap without modification.

Who It's For

This replacement is ideal for owners of Dell Inspiron 5490, G3 3500/3590 and G5 5500/5505 series laptops who originally had the smaller 3-cell, 51Wh battery and need a like-for-like swap. It suits users who prioritize correct fit and validated part numbers over extending runtime with a larger pack.

People who need maximum battery life or who have a laptop originally equipped with the 68Wh 4-cell MV07R option should look elsewhere; this 51Wh pack will not match the longer runtime of a 4-cell battery and customers should verify their original battery label before purchasing.

Pros & Cons

Pros

• Direct compatibility with multiple Dell part numbers makes it easy to find the correct replacement.
• CE and FCC certification adds confidence on safety and regulatory compliance.
• Warranty and return window reduce risk if the pack fails early or is incompatible.
• Compact 3-cell design maintains the laptop's original weight and balance.

Cons

• Some customers report mixed battery life and occasional failure to hold charge, suggesting variable quality between units.
• Lower 51Wh capacity will deliver less runtime than the alternative 68Wh 4-cell option available for some models.

Specifications

Brand	OUWEE
Battery type	Li-ion
Voltage	11.4V
Capacity	51Wh / 4255mAh
Compatible part numbers	266J9, 0415CG, C9VNH, 0PN1VN, 0M4GWP, MV07R
Replacement models	Dell Inspiron 5490; G3 3500, 3590; G5 5500, 5505; various Inspiron 15 series
Warranty	30 day refund, 12 month replacement

Our Verdict

The 266J9 11.4V 51Wh replacement is a practical, cost-effective choice for users who need a like-for-like Dell battery swap and value safety certifications and warranty support. It is best when the original pack is a 3-cell 51Wh unit; those seeking longer runtime should confirm their laptop can accept the larger 68Wh option instead.

Frequently Asked Questions

Will this battery fit my Inspiron 5490?
It will fit Inspiron 5490 and compatible models that originally used the 51Wh 3-cell battery; check your original battery label to confirm part number before ordering.

How long is the warranty?
The battery comes with a 30 day refund policy and a 12 month replacement warranty from the seller.

Is this the higher capacity 68Wh option?
No, this pack is 51Wh; the 68Wh 4-cell option is a different battery and must be selected separately if your laptop originally used that pack.