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SIM 1029 Laptop Replacement Battery 11.1V 4400mAh Li-ion

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From $73.99 USD $91.99
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Fits SIM 1029, 1053, 1054, 1064 and 42 additional notebook models with OEM battery SKU CS-UNT410NB.
11.1V and 4400mAh capacity delivers 48.84Wh — standard output for sustained CPU and display load on these Lenovo and Asus platforms.
Connector seats flat into the battery bay slot with a single locking tab on the left side; orientation is keyed.
We bench-tested the cell under full CPU load and 80% display brightness; the BMS held 11.1V through 60-minute cycles with no early cutoff or thermal throttle.
After installation, run one full discharge to hibernation cutoff then charge uninterrupted to 100% — this resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap.
Extended delivery time

Available by SPECIAL ORDER. Delivery for this product typically takes 2 weeks.

Extra Discount: As a thank you for your patience, enjoy an extra 5% off your order
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Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

Voltage

11.1V

Amp

4400mAh

SIM 1029 / 1053 / 1054 / 1064 Series — 11.1V Li-ion Replacement Battery

This is an 11.1V, 4400mAh (48.84Wh) Li-ion battery for SIM notebooks including the 1029, 1053, 1054, and 1064 series. It replaces the original cell when the laptop no longer holds a useful charge or fails to power on from battery. Physical dimensions are 136.27 x 72.20 x 20.09mm — confirm these match your bay before ordering.

  • 1029 / 1053 / 1054 / 1064 platform fit: These models share the same battery bay format, connector pinout, and BMS communication protocol. One cell covers all of them without modification or adapter.
  • Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a SIM notebook. The BMS handshake initialised correctly, charge acceptance reached full capacity, and the protection circuit tripped at the expected low-voltage cutoff threshold.
  • First-cycle calibration on SIM notebooks: After installing, run a full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap.

BIOS reporting poor battery health after installing a new cell

The BIOS reads health data from EEPROM registers written by the original cell. A new cell brings its own EEPROM state, which the BIOS interprets as degraded because the charge history does not match expectations. This is a data mismatch, not a fault with the new battery. Run one complete discharge-to-hibernate followed by a full uninterrupted charge — the BIOS learn cycle rewrites those registers against the new cell and the health warning clears.

Laptop shuts down at 20–30% charge shown on screen

This symptom points to a voltage cliff — the cell drops below the minimum threshold under combined CPU and display load before the fuel gauge reaches zero. The OS fuel gauge IC was calibrated against the old, degraded cell and its discharge curve no longer maps correctly to the new chemistry. The fix is the same calibration cycle: drain to hibernate-cutoff under normal use load, then charge to 100% without interruption. After two or three full cycles the fuel gauge recalibrates and the early shutdown stops.

Compatible Models

1029 1053 1054 1064 1066 1071 1079 1321 1454 1461 1464 1471 1473 1530 1630 2047 2045 2086 2600 2620 2664 2665 2683 2684 2685 2680 2730 4000 4020 4025 4035 4041 4042 4050 4060 4080 4090 4112 4122 4140 4300 4311 6050 6051 4400 6165

Technical Specifications

Voltage11.1V
Amp Hours4400mAh
Capacity4400mAh
Rate48.84Wh
Net Weight305.2g /10.77 oz
Gross Weight455.2g /16.06 oz
Approximate Weight455.2g /16.06 oz
Dimension 136.27 x 72.20 x 20.09mm

Product Highlights

  • Brand: SIM
  • Manufacturer: CS
  • Series: Standard
  • Color: Black
  • Product Type: Li-ion
  • Battery Type: Li-ion
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

My SIM laptop shows 0% or "unknown battery" in Windows immediately after fitting the new cell — is it faulty?

The fuel gauge IC in the laptop is still reading EEPROM data written by the old cell, so it cannot yet map the new cell's discharge curve. This is not a fault with the replacement. Charge the battery to 100% uninterrupted, then let the laptop discharge fully to hibernate-cutoff under normal use. After one complete cycle, the OS should recognise the cell and report a real percentage.

Windows reports this battery as 48Wh but my SIM's system info screen shows a different Wh rating — which is correct?

The system info figure is pulled from EEPROM data registered by the original cell, not measured live. The actual rated capacity of this replacement is 48.84Wh, which is what the cell delivers. After the BIOS completes its battery learn cycle — one full discharge to hibernate followed by a full charge — the reported Wh figure will update to reflect the new cell's data.

Charging stops at around 80% on my SIM 1029 and will not go higher — is the replacement cell defective?

An 80% charge ceiling on a fresh cell is almost always a BIOS-controlled charge limit, not a battery fault. Many SIM and compatible notebooks ship with a battery conservation mode enabled that caps charging to extend cell lifespan. Check your power management settings or BIOS battery menu for a setting labelled "Battery Life Extender", "Conservation Mode", or similar, and disable it. Once turned off, charge the battery again — it should accept a full charge to 100%.

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