How to choose a charger for your lithium battery pack?
Choosing a charger for your lithium battery pack seems simple. But using the wrong one…
The 503535 3.7V 525mAh round lithium polymer battery is a compact rechargeable LiPo pouch cell specially designed for smart wearable devices, mini electronic products, portable medical equipment, and compact IoT applications. With its round-shaped structure, lightweight design, and stable discharge performance, this battery is ideal for devices with special internal space requirements.
Manufactured by Lithotop, this round LiPo battery supports customized PCM/BMS solutions, connector configurations, and international certification support for OEM and ODM projects.
| Product Type | Round Li-Polymer battery |
|---|---|
| Model number | 503535 |
| Voltage (Nominal) | 3.7V |
| Capacity (Nominal) | 525mAh |
| Dimensions | 5*35*35mm |
| Constant Discharge Current | Typically 0.5C-1C |
| Working Temperature | charge: 0-45℃; discharge: -20-60℃ |
| Certification | ROHS/UN38.3/MSDS |
Delivering superior performance consistency and longer cycle life through automated cell matching technology designed for heavy-duty industrial applications.
The 503535 3.7V 525mAh round lithium polymer battery combines compact dimensions with stable power output, making it suitable for modern smart electronic devices requiring flexible battery structures. Compared with traditional rectangular pouch cells, the round-shaped LiPo design provides better compatibility for circular or curved product housings.
Produced using high-quality lithium polymer materials and advanced manufacturing technology, this battery offers low internal resistance, stable charging and discharging performance, and reliable cycle life. The battery can also be customized with PCM protection boards, connectors, cables, labels, and packaging solutions according to customer project requirements.
| Model | Voltage(V) | Capacity(mAh) | Cell Dimension(T*D)mm | Shape |
|---|---|---|---|---|
| 253027 | 3.7 | 150 | 2.5*30 | Round |
| 253027 | 3.8 | 155 | 2.5*30 | Round |
| 303027 | 3.7 | 180 | 3*30 | Round |
| 303028 | 3.8 | 185 | 3*30 | Round |
| 303535 | 3.8 | 305 | 3*35 | Round |
| 353535 | 3.7 | 365 | 3.5*35 | Round |
| 363027 | 3.8 | 235 | 3.6*30 | Round |
| 403535 | 3.8 | 425 | 4*35 | Round |
| 473027 | 3.8 | 335 | 4.7*30 | Round |
| 503535 | 3.7 | 525 | 5*35 | Round |
| 553535 | 3.7 | 580 | 5.5*35 | Round |
| 603535 | 3.7 | 665 | 6*35 | Round |
| 604543 | 3.7 | 1050 | 6*45 | Round |
| 753535 | 3.85 | 845 | 7.5*35 | Round |
| 755040 | 3.7 | 1500 | 7.5*50*40 | Round |
*Contact us for more Round Li-ion batteries or customize your special battery!
Discover how we helps global customers solve real-world battery challenges through customized lithium battery solutions.
A European wearable electronics company was developing a compact smart tracking device with a circular internal structure. Their previous rectangular battery solution could not fit efficiently inside the housing, causing assembly difficulties and unstable positioning during vibration testing.
The customer contacted Lithotop looking for a compact round-shaped lithium polymer battery with stable performance. After reviewing the product structure and operating requirements, Lithotop recommended the 503535 3.7V 525mAh round LiPo battery with customized connector and PCM protection design.
During sample testing, the customer completed vibration testing, runtime testing, and charging cycle evaluation. Lithotop also adjusted cable positioning and insulation protection to improve assembly stability.
Before mass production, both teams confirmed connector specifications, sample consistency, and aging performance. The final product achieved improved internal space utilization and stable mass production assembly.
A US consumer electronics company was developing a compact Bluetooth communication device and required a lightweight rechargeable battery suitable for high-volume production. Their previous supplier could not provide stable documentation support for international shipment requirements.
The customer approached Lithotop because of our experience with export-certified lithium battery projects. After reviewing the project requirements, Lithotop recommended the 503535 3.7V 525mAh round LiPo battery with optimized PCM parameters and reinforced cable protection.
During sample testing, the customer completed runtime evaluation, charging stability testing, and transportation simulation testing. After entering mass production cooperation, Lithotop also supported the customer with UN38.3, MSDS, and RoHS certification documentation for global shipment and compliance requirements.
Before mass production, both teams confirmed incoming inspection standards, connector consistency, and packaging reliability. The final product successfully entered stable large-volume production and improved the customer’s international shipment efficiency.
Powering leading batteries across wearables, medical devices, IoT, and consumer electronics in 30+ countries..
Find answers to the most common questions about ordering, shipping, certifications, and working with lithotop as your battery partner.
Engineer’s will make inner BOM according to your confirmed samples. And our quality control teams continuously monitor the entire manufacturing process to ensure the each mass production is the same as samples.
LithoTop specializes in custom lithium battery solutions, including LiPo batteries, Li-ion battery packs, LiFePO4 batteries, high-rate drone batteries, curved batteries, ultra-thin batteries, and custom rechargeable battery packs for industrial and consumer applications.
LithoTop focuses on: Custom battery solutions for special applications, own developed PCB/PCM to help you with Competitive factory-direct pricing, Experience with difficult battery projects such as curved, ultra-thin, and high-discharge batteries. Long-term cooperation support for startups and established brands.
Yes. LithoTop provides fully customized battery solutions based on your device requirements, including voltage, capacity, discharge rate, dimensions, connector type, PCM/BMS protection, and special shapes such as curved or ultra-thin batteries.
Standard samples are usually available quickly about 3-7 days, while custom battery projects typically require evaluation, engineering confirmation, prototyping, and testing. The timeline depends on battery specifications, and certification requirements. Mass order is about 30 working days.
Depending on the product and project requirements, LithoTop batteries can support certifications including UN38.3, MSDS, CE, RoHS, IEC62133, UL , and other transportation or safety compliance documents.
MOQ depends on the battery model and customization level. Standard batteries may support lower quantities like 100pcs, while fully customized battery projects usually require a development MOQ. LithoTop supports both prototype projects and mass production orders.
LithoTop follows strict quality control procedures including: Incoming material inspection, Cell matching and grading Capacity, and voltage testing, Aging and performance tests, 100% Safety inspections before shipment. Quality consistency is critical for battery reliability and long-term cooperation.
Normally, we ship our batteries via DHL, UPS, FedEx, air freight, or sea , depending on order size, destination, and customer preference.
LithoTop is a professional lithium battery manufacturer with production experience in custom battery development and assembly. We provide direct factory support, engineering assistance, quality control, and customized battery solutions for global customers. We wecome you to visit our factory.
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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.
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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