OEM Custom Battery Pack Manufacturer
Custom NiCd, NiMH, LiFePO4 and Li-ion Battery Packs for OEM and Industrial Applications.
TSJ Sanjun designs and manufactures custom battery packs using NiCd, NiMH, LiFePO4 and Li-ion cells for emergency lighting, industrial equipment, personal care devices and OEM applications worldwide.
- ✓ Custom voltage, capacity, size and connectors.
- ✓ Pack design and assembly support.
- ✓ UN38.3, MSDS, CE and RoHS documents available.
We respond within 24 hours for qualified B2B projects.
Reliable Manufacturing & Quality Control
Over 20 years of experience in cylindrical cells and battery packs, equipped with high-standard production lines, strict IQC/OQC procedures, and full-process traceability for industrial projects.
Flexible Customization for Cylindrical Cells and Battery Packs
Customization size, voltage,capacity, pole pieces and BMS available.Sample lead time is generally 7–15 days to match your design and testing schedule.
Global Certifications & Safe Transport
Provide UN38.3, MSDS, CE, RoHS and transportation reports; support imports for emergency lighting, power tools and energy storage system (ESS) projects across Europe, America and Asia.
Who We Typically Work With
We specialize in serving B2B clients in need of high reliability power solutions. Our production lines are optimized for enterprise-scale production and strict quality control standards.
Emergency Lighting Manufacturers & Service Agents
Exit signs, luminaires & backup systems
High-temperature resistant battery cells, designed for continuous trickle charging and rapid discharging during critical power outages.
OEM/ODM Product Brands
Personal care, smart home appliances, flashlights and electronic products
White-label manufacturing, providing custom PCB/BMS designs to meet precise housing dimensions and power requirements.
Battery Importers & Distributors
Wholesale supply & localized distribution
A reliable bulk supply chain, providing complete UN38.3/MSDS documentation for seamless global logistics..
Industrial Equipment Companies
Medical, power tools, robotics & high-drain
High-rate discharge, shock-resistant battery pack, designed for heavy vibration and extreme operating environments.
Battery Solutions Tailored to Your Specific Industry Requirements.
As a dedicated custom battery manufacturer, TSJ SANJUN does more than just sell battery cells. With a comprehensive portfolio covering Ni-CD, Ni-MH, LiFePO4 and lithium-ion (NCM) batteries, backed by over 20 years of engineering expertise, we address the unique power challenges of mid-sized OEM/ODM brands.
Emergency Lighting and Safety
Reliability under extreme conditions is non-negotiable in the emergency lighting industry. Whether you are transitioning from Ni-CD to LiFePO4 or seeking compliant high-temperature solutions, TSJ SANJUN is your reliable partner.
Our high-temperature nickel-cadmium, nickel-metal hydride, and lithium iron phosphate battery packs are specially designed to comply with the stringent EU Regulation 2023/1542. We ensure that your exit signs and emergency lights function properly even in environments reaching 70°C.
- Compliance: Fully compliant with ICEL 1010, UL924 and IEC 61951 standards.
- Thermal stability: It exhibits stable discharge performance in high-temperature ceiling environments.
- Durability: Provide a service life of over 4 years for critical safety infrastructure.
Personal Care, Flashlights and Small Appliances
For personal care devices like electric shavers, hair clippers, and toothbrushes, the biggest challenge is the "Perfect Fit" and long-lasting power. Even a 0.5mm deviation can cause assembly failure in compact housings.
We specialize in high-energy-density Li-ion (NMC/NCM) batteries (such as 14500, 18650, and 10440) with zero-tolerance size consistency. Our custom Li-ion battery packs include integrated smart BMS for precise overcharge and overheat protection, ensuring absolute consumer safety.
- High Energy Density: Provide maximum runtime for compact wireless devices.
- Dimensional Accuracy: Consistent dimensions across batches to enable seamless mechanical assembly.
- Safety First: Multi-layer BMS protection designed for lithium-ion batteries.
NCM Cylindrical Cells for Compact High-Drain Battery Packs
Compact power tools, handheld equipment, and small motor-driven devices often require cells that can support short bursts of high current without rapid voltage drop.
TSJ Sanjun does not position itself as a dedicated power tool battery pack manufacturer. Instead, we supply high-rate cylindrical NCM cells that can be used by OEM pack builders for compact battery pack designs requiring around 5C-10C discharge performance.
Our focus is stable cell performance, consistent internal resistance, and reliable batch matching for customers who already design or assemble their own battery packs.
- High-Rate Cell Option: NCM cylindrical cells available for compact pack designs requiring around 5C-10C discharge performance.
- Consistent Cell Matching: Internal resistance and voltage sorting help pack builders improve output stability.
- For OEM Pack Builders: Suitable for customers who manage their own BMS, welding, housing, and pack assembly process.
Solar Lighting and Energy Storage (ESS)
Small-to-medium scale energy storage requires a balance of cost-efficiency and cycle life. From solar street lights to UPS backup systems, the battery manufacturer must guarantee long-term stability.
Our LiFePO4 battery packs offer typical cycle life of 2000–6000 cycles, making them the ideal long-term investment for solar applications. We provide scalable designs that are easy to integrate into existing outdoor or indoor storage enclosures.
- Long cycle life: Significantly reduces maintenance and replacement costs.
- Environmentally friendly: 100% compliant with RoHS and REACH standards, zero heavy metal pollution.
- Weather-resistant design: Reliable operation in both extremely cold and hot tropical environments.
Real-world application results demonstrate that our customized battery solutions are currently powering thousands of emergency export systems in the EU and backup power infrastructure in the Middle East.
Superior Engineering in Every Cell
At TSJ SANJUN, we believe that the strength of a custom battery pack depends on its weakest cell. That's why our manufacturing process emphasizes rigorous cell consistency screening. Before assembly, we will strictly match cylindrical batteries based on internal resistance, voltage and capacity tolerance.
In addition to high-quality raw cells, our engineering team is proficient in co-development of intelligent BMS. Whether you require high-temperature NiCd batteries for emergency lighting or high-rate discharge lithium-ion (NMC/NCM) batteries for power tools, we design protection circuits to match the precise power characteristics and safety requirements of your equipment.
NiCd
Nickel-Cadmium (NiCd)：High-temperature NiCd cells and battery packs in sizes AAA, AA, A, SC, C, D and F, widely applied in emergency lighting and safety systems.
- High temperature resistant
- Long shelf life
- Stable performance
NiMH
Nickel-Metal Hydride (NiMH)：Green NiMH cells in AAA, AA and A sizes, ideal for medical devices, personal care products and consumer electronics; low self-discharge version available.
- High energy density
- Environmentally friendly
- No memory effect
LiFePO4
Lithium Iron Phosphate (LiFePO4)：LiFePO4 cylindrical cells in models 14500, 18650, 26650, 32700, 32140. Suitable for emergency lighting, backup power, energy storage systems (ESS) and lead-acid battery replacement, offering long cycle life and high safety performance.
- Eminent safety performance
- With a typical cycle life of 2000–6000 cycles
- Good thermal stability
Li-ion NCM
Cylindrical cells in models 10440, 14430, 14500, 18650, 21700, and 26650 feature a nominal voltage of 3.7V and a capacity range of 2200–4000mAh. It’s perfect for DC fans, small household appliances and handheld power tools.
- Maximum energy density
- Compact form factor
- High-rate discharge
Advanced Manufacturing and Uncompromising Quality Control
With three production bases in Jiangmen, Anhui and Changde, TSJ SANJUN combines 20 years of battery manufacturing experience with a flexible semi-automated production system. We guarantee industrial-grade consistency while providing ultimate flexibility to handle complex custom designs that rigid automation giants cannot accommodate.
TSJ Battery factory overview: cylindrical cell production, custom pack assembly, and QC testing.
1. Custom Engineering & Rapid Prototyping
We don't just manufacture batteries; we co-develop solutions. Our engineering team designs custom BMS (Battery Management System) and optimizes mechanical layout, delivering functional custom battery pack prototypes within 7 to 15 days.
2. Precise Cell Matching and Flexible Assembly
Consistency is everything. We utilize advanced testing instruments for strict internal resistance and voltage sorting. From there, our highly skilled technicians utilize flexible assembly lines to construct complex battery geometries and delicate wiring layouts with artisan-level precision.
3. 100% QC Testing & Global Export Ready
Every batch undergoes rigorous cycle-life and extreme-temperature testing in our in-house lab. Fully backed by UN38.3, CE, and RoHS certifications, your batteries are ready for safe, hassle-free global shipping.
Certified for Global Safety & Seamless Customs Clearance.
Frequently Asked Questions About Our Battery Solutions
Expert insights to help you make informed decisions for your OEM/ODM battery projects.
Still have questions? → Talk to our engineersWhile large-scale battery factories focus on massive multi-million unit orders, they often lack flexibility and responsiveness required by medium-sized brands. TSJ Sanjun operates as a boutique custom battery manufacturer where every mid-scale project is a VIP priority. Our clients get direct access to our battery engineering team, flexible MOQs, and agile support that large factories cannot accommodate.
Navigating the EU Battery Regulation 2023/1542 is a core expertise at TSJ Sanjun. We engineer our NiCd battery solutions to meet strict industrial and emergency lighting exemptions. Simultaneously, we assist clients in transitioning to high-performance LiFePO4 battery packs maintaining necessary thermal stability at 70°C. Every pack is backed by a full compliance folder including UN38.3, MSDS, CE, and RoHS.
Precision is our hallmark. For personal care and medical device manufacturers, a 1.0mm tolerance can be the difference between success and failure. Our facility produces Li-ion (NMC/NCM) cells (14500, 18650, 10440) with industry-leading consistency. We design the entire battery pack, including bespoke BMS tailored to your device's power curves and space constraints.
For standard cylindrical battery configurations, we typically provide physical samples within 7 days . For complex custom packs requiring specialized BMS or unique enclosures, our engineering team delivers a functional prototype within 15 days . This rapid turnaround allows clients to validate products and move into mass production months ahead of competitors.
Are you ready to upgrade your battery supply chain?
If you meet any of the following criteria, you should schedule a quick project discussion with our engineering team today:
Your current supplier has issues with cell dimensional consistency, poor capacity matching, or delayed deliveries.
You need battery packs fully compliant with UN38.3, UL, CB, CE, MSDS and EU Regulation 2023/1542 for seamless global export.
You are developing new emergency lighting, personal care devices, or high-rate discharge industrial equipment that requires custom BMS design.
You're tired of the bureaucracy of "big factories" and need a reliable manufacturing partner who treats your mid-sized projects as VIP priority.
Start Your
Custom Battery Project.
Our engineering team is ready to review your specifications and provide a technical feasibility report.
24-Hour Response
Our technical sales team responds to all inquiries within 24 hours with detailed information.
Detailed Documentation
Receive comprehensive datasheets, specifications, and technical drawings for your project.
Expert Consultation
Work directly with our experienced engineers to optimize your project requirements.
Secure & Confidential
Your project information is protected with enterprise-grade security.
ISO Certified
Quality management systems certified to international standards.
Expert Support
Direct access to our engineering team for technical consultation.