Hot Selling Home Backup Solar System

18650 battery definition

18650 battery is a common lithium battery model. Its name comes from the size of the battery, where "18" represents the battery diameter of 18mm, "65" represents the battery height of 65mm, and "0" represents the battery is cylindrical. This battery was originally invented by Panasonic Corporation of Japan and is now widely used in various portable electronic devices, such as flashlights, electric toys, portable electronic devices, and 18650 battery packs are used in some two-wheeled and three-wheeled electric vehicles.



Advantages and disadvantages of 18650 batteries:

Advantages:

1. High energy: 18650 batteries store more power in a smaller volume, providing longer use time for portable electronics.

2. High power: 18650 batteries are able to provide large currents in a short period of time, suitable for applications that require fast charging and high power output.

3. High safety: The built-in BMS (battery management system) of 18650 batteries adopts a variety of safety designs to prevent battery short circuits, overcharging, and over-discharging.

4. Long life: 18650 batteries usually have a long cycle life and can still maintain a high capacity after multiple charge and discharge cycles, which is crucial to extend the service life of the device.

5. Low self-discharge rate: This means that less power is lost during storage, which is conducive to maintaining the long-term storage performance of the battery.

6. Wide operating temperature range: 18650 cells operate in an environment of -20℃~+60℃, which makes them suitable for a variety of environmental conditions.

7. Standardized models: The size and interface of 18650 batteries are standardized, users can easily replace batteries, and there are many suppliers on the market with transparent prices.



Disadvantages:

1. Limited capacity of a single cell: The capacity of a single 18650 battery is usually between 2000mAh and 3500mAh. For devices that require more power, multiple batteries need to be used in series or parallel, which may increase the volume and weight.

2. Internal resistance increases over time: As the number of charge and discharge times increases, the internal resistance of the 18650 battery will gradually increase, resulting in weakened battery performance and reduced battery life.

3. There are safety risks: If the battery is mechanically damaged, overcharged, over-discharged or short-circuited, it may cause the battery to overheat or even catch fire, especially in uncertified battery products.

4. Correct charge and discharge management is required: In order to ensure the performance and safety of 18650 batteries, appropriate charge and discharge management circuits are required, which will increase equipment and complexity and cost.

5. Environmental treatment issues: 18650 batteries of different materials contain harmful substances, such as cobalt, manganese, nickel, etc., which need to be specially treated before they can be recycled, otherwise they will pollute the environment.

The battery management system is commonly known as the battery nanny or battery butler, and BMS is the abbreviation of Battery Management System. That is to say, the battery management system is to manage the battery so that the battery can achieve a better working state and work stably.

The battery management system is an intelligent circuit board, which is mainly used to intelligently manage, monitor, and maintain the various states of the battery to prevent overcharging, overdischarging, and short circuits in the circuit, and thereby extend the service life of the battery.

The BMS (battery management system) mainly includes a control module, a display module, a wireless communication module, a data acquisition module, and electrical equipment. The control module is connected to the input end of the BMS (battery management system); the output end of the BMS is connected to the input end of the control module; the control module is connected to the battery pack and electrical equipment respectively; the BMS (battery management system) is connected to the wireless communication module and the display module respectively through the communication interface, and the output end of the acquisition module is connected to the input end of the BMS (battery management system); the BMS (battery management system) is connected to the server end through the wireless communication module.



Main functions of BMS (Battery Management System)

1. Measurement of single battery voltage;

2. Energy balance between single batteries;

3. Measurement of total voltage of battery pack;

4. Measurement of total current of battery pack;

5. SOC calculation: Accurately estimate the state of charge (SOC) of the power battery pack, that is, the remaining power of the battery, to ensure that the SOC is maintained within a reasonable range and prevent damage to the battery due to overcharging or over-discharging.

6. Dynamic monitoring of the working status of the power battery pack: During the charging and discharging process of the battery pack, the terminal voltage and temperature, charging and discharging current and total voltage of each battery in the battery pack are collected in real time to prevent overcharging or over-discharging of the battery pack.

7. Real-time data display;

8. Data recording and analysis: Select batteries with problems to maintain the reliability and efficiency of the entire battery operation.

9. Communication networking function.

Product Overview

Huawen has independent research and development capabilities and is very mature in battery management system (BMS) and protection circuit technology. These systems can not only effectively manage the charging and discharging process of the battery, but also ensure the safety of the battery during use and extend its service life. In addition, Huawen has also made certain achievements in the field of uninterruptible power supply (UPS). The company's newly launched 12VDC and 24VDC off-grid solar UPS systems are designed for various application scenarios, including but not limited to wireless access points (AP), IP iPhones, antennas, and closed-circuit television monitoring systems (CCTV).

The main components of Solar UPS-2448PoE products are: LiFePO4 battery pack, solar panel, smart MPPT controller, anodized metal casing, galvanized steel bracket.

LiFePO4 battery pack uses lithium iron phosphate as the positive electrode and carbon as the negative electrode. It is a type of lithium-ion battery with high energy density and long life. The rated voltage of each battery is 3.2V, and the charging end voltage is 3.6V~3.65V. Due to its stability and safety, it is widely used in electric vehicles, energy storage systems and portable electronic devices. LiFePO4 battery pack can store and efficiently transmit energy. Solar panels continuously provide energy to the battery pack and convert it into electrical energy. The smart MPPT controller is connected to the Android APP Solar power 2.0, which allows users to monitor the operating status of the battery pack, solar panels, and powered equipment in real time.



Below, Huawen will take this customer as an example to introduce in detail the powered devices matched by the Solar UPS-2448PoE product.

We noticed that customers have extremely high requirements for the stability and safety of power supply. Therefore, the Solar UPS-2448PoE product is specially designed with a single-channel input energy from the solar panel, which is converted into electrical energy for charging the battery pack through the intelligent MPPT controller. The battery pack transmits the electrical energy to the powered device (PD) to ensure efficient use of energy.

We collect customer requirements and product information.





Powered device
48V POE 13.5W CCTV system




Operating voltage
44V~56V


Peak current
0.5A


Maximum operating power
13.5W


Usage environment
outdoor


Operation requirement
24 hours non-stop


Connection port
RJ45


Mains electricity
non




Provide the best solution according to customer requirements.

Solar Panel Description





Solar panel
36V 150W


Cell type
Mono


Panel size
1030*760*30mm




Panel weight
7.6kg


Connector
Waterproof MC4


Cable
1000mm lenght


Waterproof grade
IP67


Transformation efficiency
≥21%


Working temperature
-40℃~+85℃


Useful years
With reasonable use, its lifespan can be as long as more than 25 years


Bracket
Embrace pole bracket


Bracket weight
Approx 15kg





Battery Description




Charging
29.2V/15A(Max)MC4 Connector




Port1&2
MC4 Positive & negative electrode


Port3
48V2A Hi-POE-RJ45


Port4
Uplink-RJ45(10mbs/100mbs)


Port5
12VDC


Port6
24VDC


POE
IEEE 802.3 BT/AT/AF


Battery pack
LiFePO4-8S1P(27Ah/30Ah-SQLFP)


Battery capacity
25.6V27Ah/30Ah(691.2Wh/768Wh)


Battery cycle
2000 times at 80% DOD


Battery size
340*300*185mm


Battery weight
Approx 10.5kg




Product Advantages


Stable power supply: UPS can provide continuous and stable power output to meet the high power requirements of equipment and ensure that equipment will not be interrupted due to power problems at critical moments.
Intelligent BMS (Battery Management System): Through advanced technical means, it monitors and manages the operating status of the battery in real time, optimizes battery performance, extends battery service life, and ensures that the battery can be used safely in various environments.
High safety performance: UPS ensures that the product can remain stable and safe under various environments, avoids safety accidents caused by battery failure, and provides users with safety protection.
Improve work efficiency: The high performance and long-life design of the battery enable the equipment to maintain efficient operation for a long time, reducing downtime caused by battery replacement and charging, thus significantly improving the overall work efficiency.
Data protection: Through the intelligent battery management system, data loss and damage can be effectively prevented, ensuring that the user's important data is fully protected and avoiding data loss caused by battery failure.
Economical and environmentally friendly: Make full use of environmental resources, convert solar energy into electrical energy, store it in batteries, and provide stable power for electronic devices.

Mini UPS: Small Power, Big Reliability — Development and Application
With the rise of smart devices and decentralized power demands, traditional large UPS systems no longer fit all applications. The Mini UPS (Miniature Uninterruptible Power Supply) emerged to fill this gap — offering a compact, smart backup solution built around modern lithium battery technologies.

1. Background and Evolution
The demand for portable power protection for small electronics like routers, smart cameras, and IoT gateways has grown rapidly. Traditional UPS systems are bulky, expensive, and often overkill for these smaller devices. Mini UPS solutions provide an ideal alternative — compact, cost-effective, and plug-and-play.

2. Technical Architecture
Mini UPS devices typically feature DC output powered by embedded rechargeable lithium batteries and are managed by a smart BMS (Battery Management System).


Battery: 18650 / 21700 lithium or LiFePO₄ cells (7.4V, 11.1V, 12.8V)
Input: DC 5V / 9V / 12V (constant current-constant voltage charging)
Output: 5V, 9V, 12V, or 24V DC
Switching: Seamless switch-over within ≤10ms
Protection: Overcharge, over-discharge, overcurrent, short-circuit, and temperature protection

Sample Specs (Huawen Mini UPS Series):
- Battery: 7.4V 5200mAh or 11.1V 7800mAh
- Input: DC 12V/2A | Output: 12V±5% (5V/9V/24V optional)
- Switching time: ≤10ms | Charging time: 4–6 hours
- Operating temperature: -10°C ~ +50°C | Interface: DC5521, USB, RJ45
3. Key Application Scenarios

Networking: Routers, modems, WiFi repeaters — stay online during outages
Security: Smart locks, cameras, doorbells — uninterrupted monitoring
Industrial IoT: PLCs, sensors, control units — ensure data continuity
Medical: Home oxygen machines, insulin pumps — critical operation backup
Smart Home: Gateways, lighting hubs, speakers — improved reliability

4. Lithium Battery Advantage



Aspect
Lead-acid
Lithium (NCM / LiFePO₄)




Energy Density
30–50 Wh/kg
120–250 Wh/kg


Cycle Life
300–500
800–3000+


Weight
Heavy
Light (1/3–1/4)


Discharge
Moderate
Stable, high current


Safety & Eco
Contains lead
No toxic elements, recyclable


Cost Efficiency
Lower upfront
Lower lifecycle cost



5. Future Trends & Huawen Solutions
As edge computing, AIoT, and smart security evolve, Mini UPS will continue to develop toward:


📱 Smart monitoring via app or cloud
📦 Ultra-compact structural design
🛡 Enhanced BMS with thermal, SOC, and SOH diagnostics
🌱 100% lithium-based and recyclable

Huawen New Power offers end-to-end Mini UPS customization, from battery pack design to PCBA integration and casing solutions. Our team supports OEM/ODM services to power your unique business scenario.

Conclusion
Mini UPS systems are no longer scaled-down versions of traditional UPS — they are smart, efficient energy tools essential for connected devices. With lithium battery advancements, their performance and reliability continue to improve. Huawen stands ready to deliver intelligent, compact backup power you can count on.

🔋 Browse Mini UPS Products | 📩 Contact for Custom Quote

Solar-Powered Lithium Battery Solutions for Remote Monitoring Stations
Huawen New Power • Design principles, sizing methods, and best practices



Contents

Introduction
Why Lithium Batteries
Key Design Considerations
System Sizing & Examples
Recommended Specs (Summary)
System Block Diagram
Work with Huawen New Power



Introduction
Remote monitoring stations—weather, environment, oil & gas, agriculture, security—often operate far from reliable grid power. A combined solar + lithium battery system provides sustainable, efficient, and long-lasting off‑grid energy for sensors, edge controllers, and communication modules.



Why Lithium Batteries for Remote Monitoring?

High Energy Density
Compact footprint with high Wh/kg — ideal for pole‑mount and enclosure‑limited sites.


Long Cycle Life
Typically 2,000–5,000 cycles depending on DoD/C‑rate and thermal profile.


Wide Temperature Range
With proper design, reliable performance across -40℃ ~ 85℃.


Low Self‑Discharge
Retains charge during low‑sunlight seasons; reduces truck‑roll maintenance.



Note: Charging below 0℃ requires dedicated low‑temperature charge strategies or self‑heating packs.



Key Design Considerations


1) Solar Panel Sizing

Base on daily energy consumption and local solar irradiance (PSH).
Include margin (10–30%) for seasonal variability and soiling.

2) Battery Capacity

Size for nighttime load and autonomy days (e.g., 2–5 days).
Prefer DoD ≤ 80% for long life; ≤ 50% for mission‑critical assets.



3) BMS & Controls

Over/under‑voltage, over‑current, short‑circuit, temperature, and cell balancing.
SoC‑aware MPPT/charge controller integration to protect the pack.

4) Environmental Protection

Enclosure IP65+; conformal coating for PCBs in coastal/dusty sites.
Thermal design for hot/cold extremes (heaters, heat spreaders, or ventilation).





System Sizing & Examples
Core Formulas



Parameter
Formula
Notes




Daily Energy (Wh/day)
Load Power (W) × 24
Adjust for duty cycle if intermittent.


Required Storage (Wh)
Daily Energy × Autonomy Days ÷ Usable DoD
Usable DoD: 0.5–0.8 typical for lithium.


Battery Ah (at system V)
Required Storage ÷ System Voltage
Round up and add 10–20% design margin.


PV Array (W)
Daily Energy ÷ Peak Sun Hours ÷ η
η (end‑to‑end efficiency) typically 0.7–0.8.



Example — Mountain Weather Station



Item
Value
Result




Continuous Load
80 W
Daily energy = 1,920 Wh


Autonomy Days
4 days
Storage = 7,680 Wh / 0.8 DoD = 9,600 Wh


System Voltage
48 V
Battery ≈ 200 Ah (add margin → 220–240 Ah)


Peak Sun Hours
4.0 h
PV ≈ 1,920 ÷ (4.0 × 0.75) ≈ 640 W (add 20% → ~770 W)



Numbers above are illustrative; site‑specific irradiance and temperature should be used for final design.



Recommended Specs (Summary)



Category
Recommendation
Rationale




Chemistry
LiFePO₄ (LFP) or NMC with BMS
LFP for longevity/thermal stability; NMC for higher energy density.


Operating Temp.
-40℃ ~ 85℃ (system-level)
Requires pack and enclosure level thermal strategy.


DoD (daily)
≤ 80% (≤ 50% for premium life)
Extends cycle life and reduces stress.


Enclosure
IP65+ aluminum/steel with insulation
Environmental robustness; EMI shielding.


Controller
MPPT with temp sensor & low‑temp charge logic
Maximize harvest; protect cells in sub‑zero charging.


Monitoring
SoC/SoH telemetry, alarms, logs
Remote diagnostics and preventive maintenance.





System Block Diagram (Inline SVG)


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PV Array Mono/Poly 200–1000 W MPPT Controller η ≈ 95–99% Temp sensor BMS UV/OV/OCP/OTP Cell balance Battery Pack LFP/NMC 48 V 100–200 Ah -40℃~85℃ Load Sensors Comms IP65+ Outdoor Enclosure, thermal design for -40℃~85℃


Work with Huawen New Power
We design and manufacture lithium battery systems tailored for remote monitoring, including low‑temperature charging solutions, self‑heating packs, and integrated telemetry. Share your load profile and site conditions; our engineers will size an optimal solar + battery system for guaranteed uptime.

Contact: info@huawennewpower.com | Website: www.huawennewpower.com


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