BTI Battery

Keep your ThinkPad running longer between charges with the BTI Battery, a premium drop-in replacement designed for popular Lenovo models. This 44 Wh Lithium Ion (Li-Ion) battery delivers dependable power for ThinkPad T550, T550S, T560, W550, and W550S laptops, using OEM-compatible dimensions and a proprietary size that ensures a tight, secure fit. Built to mirror the performance and reliability of the original battery, the BTI Battery is ideal for traveling professionals, students, and power users who demand consistent uptime without compromising safety or compatibility.

• Seamless compatibility and precise fit: Engineered as a direct replacement for the Lenovo OEM parts 45N1743, 45N1742, 45N1741, and 45N1740, this BTI Battery slides into the battery bay of ThinkPad T550, T550S, T560, W550, and W550S with no modification required. It delivers the same connector interface and discharge characteristics, ensuring dependable performance and plug-and-play convenience for busy users who value efficiency and reliability.
• High-capacity power for extended use: With a 44 Wh energy rating, the BTI Battery provides longer runtime between charges, helping you stay productive through longer work sessions, flights, or classroom days. This capacity is especially beneficial for professionals who run multiple applications, streams, or data-heavy tasks, reducing the need for frequent recharges during critical moments.
• Advanced Li-Ion chemistry for steady performance: Built on Lithium Ion (Li-Ion) chemistry, this battery delivers consistent voltage delivery and stable energy output over its cycle life. Li-Ion cells are known for low self-discharge, reliable performance at varying temperatures, and a practical balance between weight and energy density—ideal for ultraportable ThinkPad configurations used in everyday business, education, and personal computing tasks.
• Proprietary size for secure installation: The BTI Battery uses a proprietary battery size that’s tailored to the ThinkPad battery compartment, providing a snug, secure fit and dependable contact with the motherboard. This design minimizes wobble, prevents loose connections, and ensures safe operation during travel or impact, so you can rely on steady performance in daily use or on the move.
• Safety-focused design and reliability: Built with protective features intended to guard against common battery issues—overcharge, short-circuit, and thermal risks—the BTI Battery helps protect both the battery and your laptop. With high-quality cells and careful engineering, this replacement battery supports safe charging, storage, and operation, giving you peace of mind whether you’re commuting, presenting, or working remotely.

Technical Details of BTI Battery

• Battery chemistry: Lithium Ion (Li-Ion)
• Capacity: 44 Wh
• Compatible OEM numbers: 45N1743, 45N1742, 45N1741, 45N1740
• Compatible models: ThinkPad T550, T550S, T560, W550, W550S
• Form factor: Proprietary battery size

How to install BTI Battery

• Power down your laptop completely and unplug all power sources before starting the replacement.
• Close the lid, flip the device over, and remove the screws securing the back cover. Use proper tools and work on a clean, static-free surface.
• Carefully lift the back cover to expose the battery bay, then disconnect the current battery connector from the motherboard and release any battery release latches.
• Remove the old battery and align the BTI Battery with the battery bay, ensuring the connector line up with the motherboard socket. Connect the new battery’s cable firmly and place it securely into the bay.
• Reattach the back cover and screws, then plug in the AC adapter and power on the laptop. Allow the battery to self-calibrate by charging to 100% before normal use and avoid heavy discharge cycles during the first few charging sessions.
• If your device requires a calibration routine, follow your ThinkPad’s user manual for optimized battery reporting and longer-term accuracy of charge indication.

Frequently asked questions

• Q: Is the BTI Battery a direct replacement for OEM parts?

  A: Yes. The BTI Battery is designed as a drop-in replacement for Lenovo OEM numbers 45N1743, 45N1742, 45N1741, and 45N1740, and it fits compatible ThinkPad models including T550, T550S, T560, W550, and W550S without circuit or connector modification.

• Q: What runtime can I expect with the 44 Wh capacity?

  A: Runtime varies based on usage, settings, and workload. Heavier tasks like media editing or gaming will drain the battery faster, while mixed productivity tasks and light browsing will extend the period between charges. The 44 Wh rating is designed to offer a solid balance of portability and endurance for typical day-to-day work.

• Q: Is Li-Ion the best choice for this ThinkPad battery?

  A: Lithium Ion (Li-Ion) is a common, reliable chemistry for notebook batteries, offering good energy density, lower weight, and effective cycle life when used within recommended temperature ranges. It provides stable power delivery and minimal memory effect, making it a dependable choice for ThinkPad replacements.

• Q: How should I care for my BTI Battery after installation?

  A: For best results, avoid exposing the battery to extreme temperatures, store the device in a cool, dry place, and perform regular cycles of charging and discharging in typical usage. Keep the firmware and BIOS of your ThinkPad updated to maintain accurate battery reporting and charging behavior.