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.
Reliable Manufacturing & Quality Control
Experienced 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 times depend on cell type, pack complexity, and project scope.
Global Certifications & Safe Transport
Provide UN38.3, MSDS, CE, RoHS and transportation documents; 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 engineering expertise in cylindrical battery solutions, 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 developed for emergency lighting OEM projects where standby reliability and thermal performance matter. We review your application with your engineering team and align chemistry selection and documentation with EU Battery Regulation 2023/1542 project requirements. Selected designs are intended for reliable operation in high-temperature ceiling and industrial environments.
- Compliance support: We can discuss ICEL, UL924 and IEC 61951 requirements for your project and provide relevant test documentation where applicable.
- Thermal stability: It exhibits stable discharge performance in high-temperature ceiling environments.
- Durability: Designed for long-term standby and emergency discharge in safety applications.
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 consistent dimensions across batches. Our custom Li-ion battery packs include integrated smart BMS for precise overcharge and overheat protection, ensuring robust protection features.
- 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 long cycle life suitable for solar and backup applications, 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: RoHS and REACH documentation can be provided for review on qualifying projects.
- Weather-resistant design: Reliable operation in both extremely cold and hot tropical environments.
Our cylindrical cells and custom packs support emergency lighting, backup power, and industrial OEM projects worldwide.
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 long cycle life for backup and ESS applications
- 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 decades 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, sample and prototype timelines depend on configuration and are confirmed during project review.
2. Precise Cell Matching and Flexible Assembly
Consistency is everything. We utilize advanced testing equipment for strict internal resistance and voltage screening. Then, our highly skilled technicians employ flexible production lines to construct complex battery geometries and intricate wiring layouts artisan-level precision.
3. In-House QC Testing and Export Documentation
We maintain in-house capability for cycle life and extreme temperature testing, applied according to project scope and agreed sampling plans. Documents such as UN38.3, MSDS, CE, and RoHS can be provided for review on qualifying export projects.
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.
EU Battery Regulation 2023/1542 sets requirements for batteries placed on the EU market, including chemistry choice, labeling, and documentation expectations that vary by application. At TSJ Sanjun, we review your project—such as emergency lighting, backup power, or industrial equipment—and recommend suitable Ni-Cd, NiMH, or LiFePO4 options based on your voltage, temperature, and standby requirements. Documents such as UN38.3, MSDS, CE, and RoHS can be provided for review on qualifying projects. Where high-temperature or long-term standby performance is needed, we discuss appropriate cell grades and pack design with your team. Final market compliance remains the OEM's responsibility for the complete product; we provide engineering input and test documentation to support your qualification process.
Precision is our hallmark. For personal care and medical device manufacturers, a tight dimensional control can be the difference between success and failure. Our facility produces Li-ion (NMC/NCM) cells (14500, 18650, 10440) with consistent batch matching. We design the entire battery pack, including bespoke BMS tailored to your device's power curves and space constraints.
Sample and prototype lead times depend on cell type, pack complexity, BMS requirements, and mechanical design. After engineering review, we confirm a realistic schedule for your configuration—covering cell availability, pack assembly, and any required testing—before production sampling begins.
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 export documentation such as UN38.3, UL, CB, CE, MSDS, and EU Battery Regulation 2023/1542 support for your target market—we can provide relevant documents for review on qualifying projects.
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.
Share your application and initial battery requirements. Our technical sales team will review the information and follow up by email.
Application-Based Review
Tell us the application, target specifications and expected quantity.
Requirement-Based Guidance
We will assess whether an existing product or custom solution is the better fit.
Direct Email Follow-Up
You can reply to our email later with drawings, photos or an existing specification.
Prefer email? sales@batterytsj.com
Handled Confidentially
Your inquiry is used to evaluate and respond to your battery project.
Quality Management
Supported by TSJ manufacturing and quality-control processes.
Technical Sales Support
Discuss product fit, customization and next-step information with our team.