We guarantee that this battery is top quality, Brand New, and free from defects in materials and workmanship for a period of 10 years from the date of purchase. In the unlikely event that the battery is found to be defective due to manufacturing issues, the battery will be replaced at no additional cost to the customer, provided the defect is not caused by misuse, improper installation, or failure to follow the provided instructions.

This warranty does not cover batteries that have been poorly maintained, charged incorrectly, reverse polarized, improperly installed, stored or used in excessive heat, physically damaged, or subjected to fire, freezing, water damage, tampering, terminal damage, failure to maintain the correct charge, or use exceeding the rated charge/discharge cycles. A team of technicians is available to provide technical support when needed. Proof of purchase will be requested.

The customer is responsible for shipping fees to the service center. If the product is confirmed to be defective, replacement shipping fees will be covered.

DIY Assembly Notice: DIY battery packs must have the cells balanced (same voltage) before assembly. Returns due to improper assembly or errors are not accepted. Our technicians detect voltage, internal resistance, and appearance before every shipment to ensure single cell quality. You can test the cells within 15 days of arrival; after this period, the batteries are considered to be in good order without issue, and returns/refunds will not be provided.

Returns are only accepted for unused cells (electrodes intact, no welding, no wear, and in good physical appearance). Buyers are responsible for return shipping costs.

Warranty Exclusions & Conditions:

• Warranty Period: 5 years from delivery. If a single cell capacity falls below 80% of its initial capacity, please provide test images or video for verification and solution.
• Shipping Damage: If any item is missing or damaged during transit, please contact us immediately with photos or videos. We will arrange a reshipment, replacement, or refund accordingly.
• Non-Returnable Scenarios: Damage due to assembly errors (e.g., protection board wired incorrectly causing damage, charger failure, unbalanced assembly) or battery bulging/welding due to charging without a protective BMS.

* Please note: These are prototype batteries without protection boards. You will need to purchase a compatible BMS. Please consult us for details. Placing an order implies agreement to these terms.