72Wh 61++ 01AV427 01AV425 Battery for Lenovo ThinkPad T480 T470 P51S P52S T570 T580 A485 A475 TP25 Series SB10K97584 SB10K97585 01AV490 01AV492 X50M08812 4X50M08812 01AV422 01AV423 01AV428 Review

Replacing a ThinkPad T480 battery sounds straightforward — swap out a degraded cell, get your laptop's legendary all-day runtime back. But third-party replacement batteries for Lenovo's dual-battery system are a minefield, and this 72Wh 61++ unit sits right in the middle of that tension.

What You're Actually Getting

This is the external (rear) battery for the T480 and compatible ThinkPad models — the larger of the two batteries in Lenovo's famous "Power Bridge" dual-battery setup. At 72Wh, it's the 61++ grade (6-cell, high capacity), carrying part numbers like 01AV427, 01AV425, and SB10K97584/SB10K97585 among others. The compatibility list is broad: T470, T480, T570, T580, P51S, P52S, A475, A485, and the TP25.

The appeal is obvious. Genuine Lenovo batteries are frequently out of stock, and when available, they command a steep premium. A third-party 72Wh cell at a fraction of the price looks like an easy win — especially for a laptop that's already several years old and likely running on a heavily degraded original battery.

The Dual-Battery Trap — Know Before You Buy

Here's what the product listing won't tell you clearly: the T480's dual-battery system is deceptively complex. The external rear battery and the internal front battery don't function independently — they interact through Lenovo's firmware in specific ways. Get one working and the other misbehaving, and you're in for a frustrating troubleshooting loop.

A real user on r/thinkpad ordered both an external (KingSener 61++) and an internal battery from a third-party seller. The external battery performed acceptably, but the internal battery refused to charge beyond 22% — and then drained to zero while plugged in. Pin-hole resets, reinstalls, nothing fixed it. The lesson here is pointed: the external 61++ batteries from third parties tend to fare better than the internal units, but even then, firmware compatibility and charging behavior can be unpredictable.

If you're buying just the external battery (which this product is), that's the safer bet. But go in with realistic expectations — "works fine" and "charges to exactly 72Wh like a genuine part" are two different things.

Build and Fit

The physical form factor matches the OEM unit closely. The connector layout and retention clips are designed to slot into the T480's battery bay without modification. Based on available information, the build quality is typical for third-party ThinkPad batteries — serviceable plastic housing, standard 6-cell arrangement, and a weight profile similar to the original.

Who Should Buy This — and Who Shouldn't

This battery makes sense for a fairly specific buyer:

• Your original 61++ battery is dead and Lenovo's stock is depleted — a common situation for T480 owners right now.
• You only need the external battery, not both the internal and external simultaneously.
• You're comfortable with the risk that capacity may fall short of the rated 72Wh, and that ThinkPad's battery health reporting may flag it as non-genuine.

Skip it if you're a professional relying on consistent battery life throughout a full workday, or if you've already had bad experiences with third-party ThinkPad batteries. The T480's firmware can be unforgiving with cells it doesn't recognize properly.

Practical Buyer Tips

If you do pull the trigger, a few things worth doing upfront: update your ThinkPad's BIOS/UEFI to the latest version before installing — older firmware versions are more likely to reject or misreport third-party batteries. Run a full charge-discharge cycle twice before drawing conclusions about capacity. And if you're pairing this with a new internal battery, source them from the same manufacturer if possible, since mixing brands in the dual-battery system introduces additional compatibility variables.

Frequently Asked Questions

Q: Is this the internal or external battery for the ThinkPad T480?

A: This is the external (rear) battery — the larger 72Wh unit. The T480 uses a dual-battery "Power Bridge" system with a separate smaller internal battery at the front of the chassis.

Q: Will this battery work with ThinkPad T470 as well as T480?

A: The compatibility list includes T470, T480, T570, T580, P51S, P52S, A475, A485, and TP25. Always verify your specific model's part number against the listed SKUs (01AV427, 01AV425, etc.) before purchasing.

Q: Do third-party batteries cause issues with Lenovo's firmware?

A: They can. Lenovo's BIOS may display warnings or misreport charge levels with non-genuine batteries. Updating to the latest BIOS before installation reduces — but does not eliminate — the risk.

Q: Is the external 61++ battery more reliable than the internal battery from third parties?

A: Based on community reports, yes — the external battery tends to have fewer compatibility issues than third-party internal batteries for the T480. The internal unit's charging behavior appears more sensitive to firmware handshakes.

Q: What should I do if the battery won't charge past a certain percentage?

A: Try a full BIOS update, perform the pin-hole reset on the underside of the laptop, and reinstall the battery. If the issue persists, it may indicate a firmware incompatibility — and unfortunately, a different battery brand may be necessary.

A Note on This Review

This review is based on limited sources available at the time of writing — primarily community discussions from ThinkPad users dealing with third-party battery replacements. As more user experiences with this specific product become available, we'll update this page with richer, more detailed insights on real-world capacity, longevity, and firmware behavior.

If you've used this battery in your T480 or another compatible model, share your experience in the comments below — your input genuinely helps other buyers make a more informed call.

— Tech Lead Editor, CPrice