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Custom 21700 31P 5000mAh 3C Battery Pack
The 21700 3S1P 10.8V 5000mAh 3C Li-ion Battery Pack is a rechargeable cylindrical lithium-ion battery pack designed for applications that require higher voltage, long runtime, and stable medium-rate discharge performance. Built with Grade-A 21700 cells in a 3S1P configuration, this battery pack provides 10.8V nominal voltage, 5000mAh capacity, and 3C discharge capability for robotics, handheld terminals, portable medical devices, industrial equipment, and custom electronic systems.
As a professional custom lithium battery manufacturer, LithoTop provides OEM/ODM 21700 battery pack solutions with customized connectors, wire lengths, labels, insulation structure, shrink wrap, casing, and packaging.
Additional information
| Product Type | Lithium Ion Battery Pack |
|---|---|
| Model number | 21700-3S1P |
| Voltage (Nominal) | 10.8V |
| Charge Voltage | 12.6V |
| Capacity (Nominal) | 5000mAh |
| Dimensions | Max. 42.5*42.5*75mm |
| Constant Discharge Current | Max. 3C, 15A |
| Working Temperature | -20°C~60°C |
| Certification | ISO9001/ISO14001 |
Professional Lithium Ion Battery Solutions
LithoTop designs and manufactures premium lithium-ion battery solutions using Grade A cells and self-developed BMS technology. From prototype to mass production, we provide customized OEM & ODM battery packs with superior safety, long cycle life, and reliable performance for robotics, medical devices, wearable electronics, IoT, energy storage, and industrial applications.
The 21700 3S1P 10.8V 5000mAh Li-ion battery pack is designed for devices that need a higher working voltage than 1S or 2S battery packs while still maintaining compact size and reliable energy output. Compared with traditional 18650 battery packs, 21700 cells can provide higher capacity and better energy utilization, making them suitable for modern portable equipment and industrial electronic devices.
With a 3S1P configuration, this battery pack delivers 10.8V nominal voltage, which is suitable for systems requiring stronger voltage support for motors, controllers, sensors, communication modules, displays, and power management circuits. The 5000mAh capacity provides extended runtime, while the 3C discharge rate supports stable continuous output for medium-load applications.
LithoTop applies strict production control during cell selection, voltage matching, capacity testing, internal resistance testing, spot welding, aging inspection, and final performance verification. These processes help ensure stable battery quality, reliable safety protection, and consistent mass production performance.
- 21700 High Energy Density Cells
Provides higher capacity and better energy utilization compared with many smaller cylindrical cell options. - 3S1P 10.8V Battery Pack Design
Suitable for electronic systems requiring higher voltage than 1S or 2S lithium battery solutions. - 5000mAh Long Runtime Capacity
Supports extended operating time for portable equipment and industrial electronic devices. - 3C Stable Discharge Capability
Provides reliable medium-rate output for motors, controllers, sensors, displays, and communication modules. - Strict Cell Matching
Voltage, capacity, and internal resistance are matched to improve battery pack consistency and safety. - Reliable Pack Assembly
Controlled spot welding, nickel strip selection, insulation design, and aging inspection help improve pack reliability. - Custom Battery Pack Solutions
Supports customized connectors, cable length, labels, casing, shrink wrap, and packaging for OEM projects.
- Service robots
- Educational robotics platforms
- Industrial handheld terminals
- Portable medical devices
- Inspection and testing equipment
- Wireless monitoring systems
- Security equipment
- IoT gateway systems
- Portable measuring instruments
- Custom electronic equipment
Battery Cell Choices
LithoTop offers a complete range of cylindrical lithium-ion cells to meet different power, capacity, and performance requirements. Our engineering team helps customers select the most suitable cell based on energy density, discharge current, cycle life, and application environment.
| Cell Type | Typical Capacity | Key Advantages | Typical Applications |
|---|---|---|---|
| 14500 | 600–1200mAh | Compact size, lightweight | Portable electronics, medical devices, flashlights |
| 18650 | 1800–3500mAh | Cost-effective, mature technology | Robotics, IoT devices, industrial equipment |
| 21700 | 4000–6000mAh | Higher capacity and energy density | AGVs, energy storage, power tools, e-mobility |
| 26650 | 3000–6000mAh | High discharge capability | Industrial equipment, backup power systems |
Battery Assemble
Flexible Lithium-Ion Battery Pack Customization
Every application has unique power requirements. At LithoTop, we provide complete custom lithium-ion battery pack solutions designed around your product’s voltage, capacity, size, discharge rate, connector type, and communication requirements. Whether you need a single cylindrical cell, a protected battery, or a fully assembled battery pack, our engineering team can customize every component to perfectly match your device.
Customization Options
- Battery Cells: 18650, 21700, Li-ion cylindrical cells
- Voltage: 3.6V, 3.7V, 7.2V, 7.4V, 10.8V, 11.1V, 14.4V, 14.8V, 22.2V, 24V, 36V, 48V and more
- Capacity: From mAh to over 50Ah according to your application
- Battery Configuration: 1S–20S, multiple series and parallel
- PCM / BMS: Hardware BMS, Smart BMS
- Connectors: JST, Molex, XT30, XT60, and customized connectors
- Cables: Customized wire length, AWG size, silicone or PVC cables
- Packaging: Heat shrink, PVC, plastic or aluminum case
- Branding: Custom labels, laser printing and OEM logo service
With years of experience in custom lithium-ion battery manufacturing, LithoTop helps customers shorten development cycles, reduce engineering costs, and deliver reliable battery solutions for industrial, medical, consumer electronics, robotics, IoT, security systems, power tools, and many other demanding applications.
Complete Custom Lithium-Ion Battery Pack Solutions
LithoTop provides comprehensive OEM and ODM lithium-ion battery solutions, covering every stage from premium battery cells to fully customized battery packs. Whether your project requires a single cylindrical cell, a protected battery with PCB, or a complete battery pack with connectors and housing, our engineering team delivers reliable solutions tailored to your exact application.
We offer flexible customization services including battery cell selection, BMS design, PCB protection circuits, wire harnesses, connectors, heat-shrink packaging, and complete battery pack assembly. Every battery pack is engineered to meet specific requirements for voltage, capacity, discharge rate, dimensions, communication protocols, and safety standards.
To ensure maximum compatibility, LithoTop supports a wide range of industry-standard connectors including JST, Molex, XT30, XT60, SM, PH, XH, KET, and many other customized interfaces. Our hardware and software engineering teams also develop custom protection PCBs and smart BMS solutions with overcharge, over-discharge, over-current, short-circuit, temperature protection, cell balancing, Bluetooth, CAN Bus, SMBus, UART, and other intelligent communication functions.
With strict incoming material inspection, automated production equipment, and 100% functional testing, every custom lithium-ion battery pack is manufactured to deliver high safety, stable performance, long cycle life, and reliable operation for demanding applications worldwide.
Our Customization Includes
- Premium 18650 & 21700 Lithium-ion Cells
- Hardware BMS & Smart BMS Design
- Custom PCB Protection Circuit Development
- Wire Harness & Connector Customization
- Heat Shrink & Battery Housing Assembly
- Battery Pack Mechanical Design
- OEM Logo & Laser Printing
- Communication Protocol Integration: CAN Bus / UART
- Certification Support: UN38.3, CE, RoHS, IEC62133, UL
- One-Stop OEM & ODM Battery Manufacturing
Customer Development Story
Discover how we helps global customers solve real-world battery challenges through customized lithium battery solutions.
01 – Portable Medical Device Project from the United Kingdom
A UK medical device company was developing a portable diagnostic device used by healthcare professionals during field visits and community screening programs. The device included a display, sensor module, communication function, and data processing board. The main challenge was that the battery needed to provide stable 10.8V power while keeping the device compact and easy to carry.
The customer contacted LithoTop after testing several standard battery packs that were either too bulky or unable to meet the required runtime target. They needed a custom lithium battery manufacturer that could evaluate electrical performance, safety protection, and mechanical integration together.
LithoTop analyzed the device’s working current, standby current, charging method, enclosure space, cable routing, and expected daily usage cycle. After evaluation, LithoTop recommended the 21700 3S1P 10.8V 5000mAh 3C Li-ion battery pack. The 21700 cell format provided strong capacity in a compact cylindrical structure, while the 3S configuration matched the customer’s system voltage requirement.
During sample development, LithoTop optimized wire length, connector type, insulation structure, and battery label. Sample batteries were tested through continuous runtime simulation, voltage stability checking, charging compatibility testing, temperature monitoring, and installation fit verification.
Before mass production, both teams confirmed samples, pack dimensions, connector specifications, labeling details, and incoming inspection standards. The final battery solution helped the customer achieve stable operation during long diagnostic sessions. For the customer, this improved device reliability, reduced charging interruptions, and supported a smoother product launch.
02 – Industrial Handheld Terminal Project from Germany
A German industrial equipment company was developing a handheld terminal for factory maintenance, barcode scanning, and equipment inspection. The product required higher voltage support for the display, processor, wireless module, and sensor interface. Their previous battery pack caused inconsistent runtime during long shifts and did not fit well inside the handle structure.
The customer approached LithoTop because they needed a customized 21700 battery pack that could provide better runtime while matching a narrow mechanical space. LithoTop reviewed the device’s current consumption, wireless transmission peaks, charging circuit, handle dimensions, connector position, and production assembly process.
Based on this evaluation, LithoTop recommended the 21700 3S1P 10.8V 5000mAh 3C Li-ion battery pack. The 10.8V platform supported the customer’s electronics efficiently, while the 5000mAh capacity provided enough working time for daily industrial use. The 3C discharge capability was suitable for the device’s moderate load and short current peaks.
During prototype development, LithoTop adjusted the battery pack arrangement, cable outlet direction, connector type, and outer insulation protection. Sample testing included runtime testing, wireless transmission pulse testing, vibration simulation, repeated charge-discharge cycling, and installation fit checking.
Before mass production, the customer confirmed approved sample performance, final dimensions, connector durability, packaging method, and batch quality standards. LithoTop then controlled production according to the confirmed golden sample.
The final battery pack helped the handheld terminal operate more reliably during full-shift use and reduced the need for frequent charging. For the customer, this improved technician efficiency, reduced field service concerns, and made their product more competitive in industrial maintenance markets.
Why Choose LithoTop for 21700 3S1P Li-ion Battery Pack Solutions?
A reliable 21700 3S1P Li-ion battery pack requires more than simply connecting three cells in series. Battery performance depends on cell quality, voltage consistency, internal resistance control, nickel strip selection, spot welding quality, connector reliability, insulation protection, and final aging inspection.
LithoTop supports customers from sample design to mass production with Grade-A 21700 cells, customized BMS solutions, strict production inspection, and flexible OEM/ODM assembly. Our engineering team can help evaluate operating current, installation space, charging method, protection requirements, connector type, and real application conditions before confirming the final battery design.
Manufacturing Capability
LithoTop has strong lithium battery manufacturing capability, combining advanced production equipment, experienced engineering teams, strict quality control, and flexible OEM & ODM services. From cell selection to final battery pack assembly, every process is carefully managed to ensure stable quality, reliable performance, and consistent mass production.
120,000+ Daily Production Capacity
LithoTop supports stable large-scale production for LiPo batteries, Li-ion battery packs, LiFePO₄ batteries, and customized battery solutions, helping customers meet both small-batch development and mass production needs.
Advanced Battery Pack Assembly Lines
Our production lines are equipped for cell sorting, spot welding, soldering, PCM/BMS assembly, insulation protection, labeling, aging, and final packaging, ensuring efficient and standardized battery production.
In-House BMS & PCB Production
LithoTop has its own BMS manufacturing facility with 10 production lines, supporting 1S–25S, 1A–300A battery protection solutions for Li-ion, LiFePO₄, and sodium battery packs.
Automated Cell Matching
Before battery pack assembly, cells are carefully matched by voltage, capacity, and internal resistance to improve battery consistency, safety, and cycle life.
Precision Welding Technology
We use professional spot welding and nickel strip connection processes to ensure strong electrical conductivity, low resistance, and stable high-current performance.
Strict In-Process Quality Control
During production, our quality team monitors key processes including welding quality, PCM/BMS connection, insulation, voltage consistency, appearance, and structural assembly.
Comprehensive Testing Capability
Each battery undergoes voltage testing, internal resistance testing, capacity testing, charge/discharge testing, aging tests, and final inspection before shipment.
OEM & ODM Customization
LithoTop supports customized voltage, capacity, battery structure, discharge current, connectors, wire length, housing, labels, packaging, and communication protocols.
Production Process
- Incoming Material Inspection: Cells, PCM/BMS, wires, connectors, nickel strips, and packaging materials are inspected before production.
- Cell Sorting & Matching: Cells are matched by voltage, capacity, and internal resistance to ensure pack consistency.
- Battery Pack Assembly: Cells are connected through professional welding, soldering, and insulation processes.
- PCM/BMS Integration: Protection boards are installed and tested according to battery safety requirements.
- Aging & Performance Testing: Batteries are tested under charging and discharging conditions to verify stability.
- Final Inspection: Appearance, labeling, voltage, capacity, polarity, and packaging are checked before shipment.
- Safe Packaging & Delivery: Mass Production Batteries are packed according to transportation requirements with support for UN38.3 and MSDS.
Quality Assurance
LithoTop follows strict quality management throughout the entire manufacturing process. Every battery is tested before shipment to ensure true capacity, stable voltage output, low internal resistance, safe operation, and reliable long-term performance.
Why It Matters for Customers
With strong manufacturing capability and in-house BMS development, LithoTop helps customers reduce communication costs, shorten product development time, improve production consistency, and receive more reliable customized battery solutions from prototype to mass production.
More Customer Cooperation Cases
LithoTop has successfully delivered customized lithium-ion battery pack solutions to customers in more than 30 countries. From prototype development to mass production, our engineering team helps customers solve complex power challenges across industrial, medical, robotics, and energy storage applications.
AGV & Autonomous Mobile Robots
A European AGV manufacturer required a high-capacity lithium-ion battery pack with CAN communication, stable discharge performance, and long cycle life. LithoTop developed a customized 24V battery pack with an intelligent BMS, helping improve operating time and reduce maintenance costs.
Medical Diagnostic Equipment
A medical device company needed a compact battery pack with exceptional reliability and safety for portable diagnostic equipment. LithoTop engineered a customized lithium-ion solution using Grade A cells and an in-house BMS, ensuring stable power output and consistent performance throughout the product lifecycle.
Industrial Inspection Robot
An industrial automation customer required a lightweight, high-discharge battery pack capable of supporting continuous operation in demanding environments. LithoTop provided a customized 21700 battery pack with intelligent protection, enabling longer runtime and enhanced operational efficiency.
Handling Precautions & Guidelines
Find answers to the most common questions about ordering, shipping, certifications, and working with lithotop as your battery partner.
After sample approval, all production parameters are standardized. Every production batch follows the same BOM, manufacturing process, and quality inspection procedures. Batteries undergo voltage, capacity, internal resistance, aging, and final performance testing before shipment to ensure consistency.
LithoTop provides custom lithium-ion battery packs using 15270, 14500, 18650, 21700, 26650 and other cylindrical cells. We support customized voltage, capacity, discharge current, connectors, communication protocols, housing, and BMS solutions based on your project requirements.
Yes. Our engineering team can evaluate your existing battery pack and recommend an equivalent or improved battery solution while maintaining the same dimensions, connector, communication protocol, and mechanical structure whenever possible. This helps reduce redesign costs, shorten qualification time, and ensure a smooth supplier transition.
Yes. LithoTop designs high-discharge lithium-ion battery packs with high continuous and peak discharge capability for AGVs, robots, drones, industrial automation, and power equipment. We can recommend the most suitable cell based on your power requirements.
Engineering samples are typically completed within 7–15 working days. Mass production usually requires 15–30 working days depending on battery complexity, material availability, and order quantity.
Our battery packs can support CE, RoHS, UN38.3, MSDS, IEC62133, CB, KC, and other international certifications depending on your market and application requirements.
MOQ depends on the battery configuration and customization level. We support prototype development, engineering samples, pilot production, and large-volume manufacturing to help customers throughout the product development process.
Please provide your required voltage, capacity, maximum discharge current, battery dimensions, connector type, communication requirements, operating environment, and expected application. Our engineers will recommend the most suitable battery solution.
Yes. LithoTop has an in-house BMS manufacturing facility capable of developing intelligent protection boards from 1S to 25S. We support CAN, SMBus, RS485, Bluetooth, UART, and other communication protocols.
LithoTop combines premium Grade A battery cells with our own BMS manufacturing capability, enabling us to provide complete battery solutions from a single supplier. This helps reduce communication costs, shorten development cycles, and ensure better compatibility between battery cells, protection systems, and customer applications.
Related Products
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Our Factory Insight
LithoTop operates advanced lithium battery manufacturing facilities equipped with automated production lines, precision testing equipment, and strict quality control systems. From cell selection to battery assembly and final inspection, every process is carefully managed to ensure stable performance, reliable quality, and high production efficiency. With experienced engineers and strong OEM/ODM capability, we provide customized battery solutions for customers worldwide.
Global Certifications & Compliance Support
LithoTop provides comprehensive certification support for custom lithium batteries to help customers accelerate product development and global market entry. From prototype verification to mass production, our engineering team assists with battery compliance, transportation documentation, and international safety standards, reducing certification risks and shortening your project timeline.
Industry News Insight
Stay updated with the latest lithium battery industry news, product innovations, technology insights, and application trends from LithoTop. Explore expert articles, battery guides, and industry updates to learn more about custom lithium battery solutions, energy storage, UAV batteries, wearable device batteries, and advanced power technologies.
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