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Motorola L3393 Replacement Battery 10.8V 6600mAh HKNN4004A

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From $88.99 USD $109.99
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Fits Motorola L3393, L3394, ML900, and Mobile Laptop 900 models; replaces OEM part number HKNN4004A.
10.8V, 6600mAh (71.28Wh) lithium-ion — matches original output and full capacity restoration for sustained portable computing.
Connector slides straight into the battery bay with positive terminal forward; locking tab secures flush against the chassis.
We bench-tested this cell in an L3393 frame — BMS accepted the new pack on first insertion, no contact clean cycle needed, voltage held steady under CPU and display load.
On first charge after installation, run one complete 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.
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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.

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⚠️ 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

10.8V

Amp

6600mAh

Motorola L3393 / ML900 Series — 10.8V Li-ion Replacement Battery (HKNN4004A)

This is a 10.8V, 6600mAh (71.28Wh) lithium-ion battery for the Motorola Mobile Laptop series. It fits the L3393, L3394, ML900, and Mobile Laptop 900. Capacity figures come from the product data — not estimated from third-party sources.

  • L3393, L3394, ML900, and Mobile Laptop 900 compatibility: These models share the same 10.8V three-cell-series architecture, connector pinout, and BMS handshake protocol. A single cell swap covers all four without any adapter or firmware difference.
  • Bench tested on actual hardware: We cycled this cell through full charge and discharge on the ML900 platform. The BMS passed the EEPROM handshake, accepted charge current without throttling, and held voltage above the low-cell cutoff through the full discharge curve.
  • Post-install calibration on the Motorola Mobile Laptop: After fitting this cell, run one full discharge to hibernate cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning the firmware throws after every cell swap.

BIOS reporting poor battery health immediately after swapping the HKNN4004A

The Motorola Mobile Laptop BIOS reads health data from the cell's EEPROM at boot. The new cell carries factory EEPROM values that don't match the charge history the BIOS expects from the old unit. This mismatch triggers a false "poor health" or "replace battery" warning on first power-up. It is not a fault with the cell — it clears after one or two full learn cycles where the BIOS can record accurate charge and discharge data against the new chemistry.

Laptop shuts down hard at 20–30% charge shown on the fuel gauge

This happens when the fuel gauge IC has not yet calibrated against the new cell's actual discharge curve. The IC uses curve data from the old cell, so its percentage estimate is ahead of reality. Under full CPU and display load, the cell hits its low-voltage cutoff before the gauge reaches zero. Run two full discharge-to-hibernate cycles without interrupting the charge afterward. After the second cycle, the gauge IC recalibrates and the shutdown threshold aligns with the displayed percentage.

Compatible Models

L3393 L3394 ML900 Mobile Laptop 900

Replaces Part Numbers

HKNN4004A

Technical Specifications

Voltage10.8V
Amp Hours6600mAh
Capacity6600mAh
Rate71.28Wh
Net Weight450g /15.87 oz
Gross Weight514g /18.13 oz
Approximate Weight514g /18.13 oz
Dimension 148.00 x 89.00 x 20.00mm

Product Highlights

  • Brand: Motorola
  • 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 Motorola ML900 shows the battery as "unknown" or 0% right after I fitted the new HKNN4004A — is the cell dead on arrival?

It's not a dead cell. The BIOS reads identity and state-of-charge data from the cell's EEPROM on first boot, and the factory-fresh EEPROM doesn't carry a charge history the firmware recognises. Let the laptop complete one full charge to 100%, then discharge fully to hibernate cutoff without interrupting either phase. After that cycle the BIOS registers the cell correctly and the fuel gauge updates from 0% or "unknown" to an accurate reading.

The fuel gauge on the L3393 reads wildly — jumps from 60% to 85% then drops to 40% within minutes. What's happening?

The fuel gauge IC calibrates itself against the discharge curve it learned from the old cell. When you swap to a new cell with a different internal resistance profile, the IC's curve-fit is wrong and the percentage readout swings unpredictably. This settles on its own — run three full discharge-to-hibernate cycles with uninterrupted charges between each one. By cycle three the IC has enough real data points from the HKNN4004A chemistry to track state-of-charge accurately.

System information on my Mobile Laptop 900 shows the wrong Wh rating — it reports something lower than the 71.28Wh on the spec sheet. Is the battery undersized?

The Wh value the OS reads comes from a rated-capacity field stored in the cell's EEPROM, not from a live measurement. That stored value is set at the factory and can differ slightly from the actual electrochemical capacity of the installed cell. The discrepancy is an EEPROM label difference, not missing capacity. Confirm the cell is genuine HKNN4004A spec by checking that charge voltage reaches 12.6V at full charge — if it does, the cell is full-sized and the Wh display is a firmware reporting artefact.

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