21V Li-Ion Replacement Battery for Dayi Cordless Power Tools
21V Li-Ion Replacement Battery for Dayi Cordless Power Tools
21V High-Capacity Lithium-Ion Battery for Dayi Cordless Power Tools
Keep your Dayi cordless screwdriver, drill, and power tools running at full speed with this high-performance 21V Lithium-Ion Rechargeable Battery. Available in three capacity options — 3Ah, 6Ah, and 9Ah — this replacement battery is engineered for long runtimes, fast recharging, and rock-solid reliability on the job site or in the workshop.
Built from flame-retardant ABS housing and backed by an 8-layer intelligent protection system, this battery is designed to keep you working safely and efficiently, charge after charge.
Key Features
- Voltage: 21V — compatible with Dayi 21V cordless power tools
- Capacity Options: 3.0Ah (3000mAh) / 6.0Ah (6000mAh) / 9.0Ah (9000mAh)
- Battery Type: Li-Ion (Lithium-Ion)
- Model Number: DY*21V
- Discharge Current: 5–15A for consistent, stable power output
- Weight: 3.0Ah ~313g / 6.0Ah ~538g / 9.0Ah ~760g
- Flame-Retardant ABS Shell — safe, durable, and heat-resistant
- CE Certified — meets international safety standards
8-Layer Intelligent Protection System
This battery includes comprehensive built-in protections to keep your tools and workspace safe:
- ✔ Overcharge Protection
- ✔ Over-Discharge Protection
- ✔ Overvoltage Protection
- ✔ Over-Temperature Protection
- ✔ Short-Circuit Protection
- ✔ Anti-Overflow Protection
- ✔ Overcurrent Protection
- ✔ PTC Protection
Technical Specifications
| Voltage | 21V |
| Capacity | 3.0 / 6.0 / 9.0 Ah |
| Battery Type | Li-Ion |
| Charging Temperature | 0°C – 55°C |
| Discharge Temperature | -40°C – 75°C |
| Storage Temperature | 0°C – 45°C |
| Storage Humidity | ≤ 85% RH |
| Certification | CE |
| High-Concern Chemicals | None |
Compatibility
Designed as a direct replacement for Dayi 21V cordless tools. As long as the battery connector socket matches, this battery can be used with a wide range of compatible 21V electric power tools including cordless screwdrivers, drills, and gun drills.
Made in Mainland China.
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Frequently Asked Questions
Q: Which Dayi tools is this 21V lithium battery compatible with?
A: This replacement battery is compatible with Dayi 21V cordless power tools, including cordless screwdrivers and gun drills. It can also work with other 21V tools as long as the battery connector socket matches. Always verify your tool's voltage and connector type before purchasing.
Q: What capacity should I choose — 3Ah, 6Ah, or 9Ah?
A: The 3Ah option is ideal for light-duty or occasional use. The 6Ah battery offers a good balance of runtime and weight for everyday workshop tasks. The 9Ah battery delivers the longest runtime and is best suited for heavy-duty or extended professional use. Choose based on how long you need your tools to run between charges.
Q: Is a charger included with this battery?
A: Yes, a compatible charger is included with this listing. The battery supports charging in environments between 0°C and 55°C for safe and efficient charging performance.
Q: Is this battery safe to use?
A: Absolutely. This battery features a flame-retardant ABS housing and an 8-layer intelligent protection circuit covering overcharge, over-discharge, overvoltage, over-temperature, short-circuit, anti-overflow, overcurrent, and PTC protection. It is also CE certified, meeting international safety standards.
Production & Packaging Notice
To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.