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Hasee CNV4S02 Replacement Battery 15.2V 3050mAh

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From $91.99 USD $113.99
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Fits Hasee CNV4S02 and S7-2021S7 notebooks as a direct replacement for the original 15.2V lithium-ion pack.
15.2V at 3050mAh delivers 46.36Wh total — sufficient for this ultraportable form factor without voltage sag under mixed CPU and display load.
Connector orientation matches the original slot; locking tab engages flush against the battery door without forcing.
We bench-tested the cell on a CNV4S02 unit; the BMS accepted the new pack on first insertion and charged to 100% without cutoff errors.
After installation, run one full discharge to hibernation-cutoff then charge uninterrupted to 100% — this resets the BIOS battery learn cycle and clears health warnings.
Delivery time

This product ships directly from our Manufacturer’s Warehouse and is usually delivered within 5 – 8 business days to your doorstep.

Discount: As a thank you for your patience, enjoy 5% off on 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

15.2V

Amp

3050mAh

Hasee CNV4S02 / S7-2021S7 — 15.2V Li-ion Replacement Battery

This is a 15.2V, 3050mAh (46.36Wh) Li-ion battery for Hasee notebook models CNV4S02 and S7-2021S7. It replaces the original internal cell when the laptop no longer holds a charge or fails to power on from battery alone. Voltage and connector match the original specification on both supported models.

  • CNV4S02 and S7-2021S7 compatibility: Both models run the same 15.2V four-cell Li-ion architecture with identical BMS handshake requirements and connector pinout. One battery covers both variants without any hardware modification.
  • Bench tested on actual hardware: We cycled this cell through charge and discharge on a compatible Hasee unit. The BMS accepted the new cell without error flags, and the protection circuit responded correctly to both overvoltage cutoff and undervoltage protection thresholds.
  • Post-install calibration cycle: After fitting this battery, discharge the laptop fully until it hibernates on its own — do not force shutdown — then charge it uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that typically appears after any cell swap on these models.

Why the CNV4S02 shuts down at 20–30% after a battery swap

The BIOS fuel gauge IC was calibrated against the old cell's discharge curve. When a new cell goes in, the IC still uses the stored curve, which no longer matches actual cell voltage under load. Under full CPU and display load, the real cell voltage drops faster than the gauge expects, triggering a low-voltage shutdown well above the displayed percentage. One complete discharge-to-hibernate followed by an uninterrupted full charge forces the IC to relearn the new cell's curve and corrects the early cutoff behaviour.

BIOS reporting battery health as poor or unknown straight after fitting

This happens because the BIOS reads health data from EEPROM registers that were written by the original cell over its lifespan. A new cell arrives with fresh EEPROM data that does not match the degraded values the BIOS was expecting, so it flags the result as unknown or poor. It is not a fault with the replacement cell. Run two full calibration cycles — full discharge to hibernate, then charge to 100% uninterrupted — and the BIOS health reading will update to reflect the actual state of the new cell.

Compatible Models

CNV4S02 S7-2021S7

Technical Specifications

Voltage15.2V
Amp Hours3050mAh
Capacity3050mAh
Rate46.36Wh
Net Weight215g /7.58 oz
Gross Weight475g /16.76 oz
Approximate Weight475g /16.76 oz
Dimension 260.20 x 80.60 x 7.10mm

Product Highlights

  • Brand: Hasee
  • 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 Hasee CNV4S02 shows 46Wh in the battery report but the BIOS still lists the old watt-hour rating from my previous cell — is something wrong?

Nothing is wrong with the replacement cell. The Wh figure the BIOS displays is pulled from EEPROM data written by the original battery, not measured live from the new cell. After one or two full discharge-to-hibernate and uninterrupted charge-to-100% cycles, the EEPROM registers update to reflect the new cell's actual rated capacity. Check System Information again after completing those cycles and the value should read correctly.

The fuel gauge on my S7-2021S7 jumps around wildly — showing 60%, then 45%, then back to 55% within minutes of unplugging.

The fuel gauge IC needs calibration cycles against the new cell's actual discharge curve. Until it has that data, it interpolates from the old curve, which causes the erratic percentage swings you are seeing. Discharge the laptop fully until it auto-hibernates, then charge it to 100% without interruption — repeat this twice. After two complete cycles, the gauge IC locks onto the new cell's curve and the percentage readings stabilise.

The replacement battery charges fine but stops at exactly 80% and will not go higher — the charging indicator just turns off.

This is a BIOS-controlled charge limit, not a fault in the battery itself. Many Hasee laptops ship with a battery care setting active in the BIOS or a companion utility that caps charging at 80% to reduce cell stress during daily desk use. Enter the BIOS setup menu on boot, locate the battery or power section, and disable the charge limit or set the threshold to 100%. If a Hasee system utility is installed, check its settings there first — the BIOS option and the software override each other on some firmware versions.

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