Laptop Battery for Lenovo K4350A K4350 K4450 K4450A M490S K4250 11.1V 5200mAh 57Wh Replace 121500557, 121500558, 45N1113, 45N1115 2-Year Warranty

**Product Overview**
Upgrade your Lenovo laptop with a reliable, high-performance replacement battery designed specifically for the K4350A, K4350, K4450, K4450A, M490S, and K4250 series. Whether your original battery no longer holds a charge or you need extended power for on-the-go productivity, this 5200mAh / 57Wh battery offers a perfect balance of capacity, safety, and durability.

**Important Voltage Warning**
Please confirm your original battery voltage is 11.1V before ordering. Using an incorrect voltage (e. g., 10.8V or 14.4V ) may cause system instability or permanent damage to your laptop. This battery is designed exclusively for 11.1V systems.

**Compatible Laptop Models**
- Lenovo K4350A
- Lenovo K4350
- Lenovo K4450
- Lenovo K4450A
- Lenovo M490S
- Lenovo K4250

**Replacement Part Numbers**
121500557, 121500558, 45N1113, 45N1115, 45N1117, 45N1119, 121500559, 121500560, L11M4P71, L11S4P71, L11L4P71, L11C4P71, L11M4P72, L11S4P72, L11L4P72, L11C4P72, SB10K97581, SB10K97582, SB10K97583, SB10K97584, SB10K97585, SB10K97586, SB10K97587, SB10K97588, SB10K97589, SB10K97590, 5B10K97581, 5B10K97582, 5B10K97583, 5B10K97584, 5B10K97585, 5B10K97586, 5B10K97587, 5B10K97588, 5B10K97589, 5B10K97590

**Technical Specifications**
| Specification | Detail |
| --- | --- |
| Battery Type | Li-ion (Lithium-ion) |
| Voltage | 11.1V |
| Capacity | 5200mAh / 57Wh |
| Cell Count | 6 cells |
| Color | Black |
| Weight | Approx. 330g |
| Warranty | 2 Years |

**Comparison Table: Original vs. Replacement**
| Feature | Original Battery (Aged) | Our Replacement |
| --- | --- | --- |
| Capacity | 4400mAh (degraded) | 5200mAh (new) |
| Runtime (typical) | 12 hours | 35 hours |
| Overcharge Protection | May fail over time | Built-in IC & BMS |
| Warranty | Expired | 2-Year Coverage |
| Price | High (OEM) | Affordable |

**Installation Tips**
1. Power off your laptop and unplug the AC adapter.
2. Remove the battery latch or unscrew the battery compartment cover (if applicable).
3. Gently slide out the old battery and disconnect the cable (if present).
4. Insert the new battery until it clicks into place.
5. Charge the battery fully (about 34 hours) before first use for optimal performance.
6.
Calibrate once a month: charge to 100%, then discharge to 10% before recharging.

**Safety & Quality**
Every battery undergoes rigorous testing for voltage stability, capacity accuracy, and safety compliance. Certified with CE, FCC, and RoHS standards, our batteries include multi-layer protection against over-voltage, over-current, short-circuit, and overheating.

**Package Includes**
- 1 x 11.1V 5200mAh Laptop Battery
(with installation guide)

**Order with Confidence**
We stand behind our product with a 2-year warranty and 30-day hassle-free return policy. If you have any compatibility questions, please contact us with your laptop model and original battery part number before purchasing.