FSKE 6.5Ah Replacement Battery for Kobalt 40V – KB540-06 / KB440-06 / KB640-03 | Compatible with 40V Power Tools

Power that lasts with the FSKE 6.5Ah Replacement Battery

Upgrade your outdoor workflow with the FSKE 6.5Ah replacement battery designed for Kobalt 40V tools. This pack combines robust power, thoughtful design, and practical features that help you tackle lawn care, yard cleanup, and seasonal maintenance with fewer interruptions. While results vary by tool and usage, many users notice smoother performance and longer runtimes in real-world tasks.

Enhanced power and practical runtime

The 40V, 6500mAh capacity is built to deliver substantial runtime across a range of tool applications. It offers up to 50% more power than the OEM 4.0Ah battery under comparable loads, helping you complete tasks more efficiently. The battery uses high-grade cells and is rated for a discharge life that can exceed a thousand cycles, making it a long-lasting option for regular outdoor work.

• 6500mAh capacity aimed at longer sessions between charges
• Up to 50% more power than the 4.0Ah OEM alternative under similar conditions
• A+ grade cells with a discharge life exceeding 1000 cycles

Compatibility and charging flexibility

This FSKE battery is designed for broad compatibility with all 40V Kobalt power tools, including string trimmers, leaf blowers, hedge trimmers, chainsaws, and lawn mowers. It also works with Kobalt 40V charger models KRC60-06, KRC40-06, and KRC840-03, giving you flexible charging options for busy workdays.

• Compatible with all 40V Kobalt tools
• Supports KRC60-06, KRC40-06, and KRC840-03 chargers
• 4 LED power indicators show remaining runtime at a glance

Smart safety and durable design

Designed with practical safety in mind, the FSKE battery features a smart BMS to guard against short circuits, overcharging, over-voltage, and overheating. The exterior uses a PC+ABS shell with an A0 fire rating, providing durability and reliable heat dissipation thanks to breathable surface ventilation.

• Smart BMS for protection against electrical issues
• PC+ABS shell with A0 fire rating for durability
• Breathable shell design supports heat dissipation during use

Real-life use and support

Whether you’re tidying up a weekend lawn, pruning a hedgerow, or clearing leaves, this 6.5Ah battery is intended to keep you moving between charges. If you have questions or encounter an issue, our customer service team is ready to help via the storefront question option or order details page.

• Visual runtime check with four LED indicators
• Support via Ask a Question or contact seller for a quick consult