Shenzhen Headquarters
Shenzhen, Guangdong, China
Li-Polymer Battery
3.8V Li-Polymer 3500mAh Slim Battery for Smart Wearables
- Product No.:EPT-2
- Cell Model:OEM / Custom
- Nominal Voltage:3.8 V
- Nominal Capacity:3500 mAh
A slim-profile Li-Polymer cell optimized for space-constrained wearable devices. Delivers the energy density modern consumer electronics demand without sacrificing safety or cycle life.
Specifications
Technical Specifications
| Nominal Voltage | 3.8 V |
|---|---|
| Capacity | 3500 mAh |
| Chemistry | Li-Polymer (LiPo) |
| Max Continuous Discharge | 1 C |
| Cycle Life | >800 cycles @ 80% capacity |
| Operating Temperature | -10°C ~ 60°C |
| Dimensions (L×W×H) | 55 × 35 × 3 mm |
| Weight | 42 g |
| Certifications | CE, UL, UN38.3, MSDS, KC |
What sets it apart
Key Features
- 3mm ultra-slim form factor for sleek device design
- High energy density: 285 Wh/L
- Low self-discharge < 3% per month
- Integrated NTC for accurate thermal monitoring
Where it shines
Applications
- Smartwatches & fitness trackers
- TWS earbuds charging cases
- AR / VR headsets
- Portable beauty devices
Our Promise
Built on scale, quality, and global reach
Four company-owned manufacturing campuses and decades of battery expertise—so your product gets the capacity, compliance, and support it deserves.
Meizhou Production Base
Meizhou, Guangdong, China
Jiangsu Manufacturing Park
Jiangsu Province, China
Vietnam Production Facility
Vietnam
Proven Scale
23+ years in batteries. 2025 revenue exceeding RMB 800 million, with industry-leading cell technology and deep engineering bench strength.
Quality Assurance
Every unit passes a 36-step inspection process with strict in-process controls—designed to ship consistently defect-free product.
Certified Systems
CNAS-accredited test lab, rigorous internal standards, and a compliance framework backed by major international certifications.
Production Capacity
Four company-owned sites in Shenzhen, Meizhou, Jiangsu, and Vietnam—daily output of 800K Ni-MH cells, 600K Ah lithium cells, and 300K battery packs.
Global Service
Worldwide product liability coverage, 1,000+ customers served, and localized support across North America, Europe, Japan, Korea, and China.
Core Product Lines
Pouch Li-polymer, cylindrical lithium, Ni-MH, and Ni-Zn cells for consumer electronics, energy storage, and industrial applications.
Contact Us
Talk to our team
Reach us by phone, email, or the form below—we typically respond within one business day.
- Customer Service Hotline
- +86 755 8888 1000
- 24/7 Custom Solutions Line
- +86 755 8888 1001
- Sales Phone
- +86 755 8888 1002
- Company Email
- sales@ept-battery.com
- Live Support (QQ)
- 800888100
- Fax
- +86 755 8888 1099
Headquarters
EPT Battery Technology Park, Nanshan District, Shenzhen, Guangdong 518000, China
Meizhou Campus
EPT Meizhou Industrial Zone, Meizhou, Guangdong 514000, China
Jiangsu Campus
EPT Jiangsu Manufacturing Park, Suzhou, Jiangsu 215000, China
Vietnam Campus
EPT Vietnam Production Facility, Binh Duong Province, Vietnam
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