People want a fast calculator to help on their custom battery design, however, since things are complicated with different voltage and capacity of each cell, we think people designing the battery packs should know some basics of lithium battery design.
If you are looking for more details, kindly visit our website.
Battery packs achieve the desired operating voltage（ie: Total Battery Pack Voltage） by connecting several cells in series( S in short ); each cell adds its voltage. Parallel( P in short) connection attains higher capacity by adding up the total ampere-hour (Ah).
to help you further understand how it works, see below explanation:
#1 For the series connection, batteries with same(almost) voltage and capacity are connected to raise the voltage of final battery packs. The positive terminal of the first battery is connected to the negative terminal of a second battery and so on until the desired voltage is reached. The final voltage is the amount of all battery voltages added together while the final capacity(Ah) remains unchanged.
#2 While for parallel connection, batteries with same(almost) voltages and capacities are connected together to increase the capacity of the overall battery pack. The positive terminals of all batteries are connected together, or to a common conductor, and all negative terminals are connected in the same kinds. The final voltage remains unchanged whilst the capacity of the assembly is the sum of all individual cells together for such parallel design.
let’s use Samsung 3.7V 2.6Ah( mAh) for example.
1S1P pack that’s 3.7V 2.6Ah battery pack
2S1P pack that’s 7.4V 2.6Ah battery pack
1S2P pack that’s 3.7V 5.2Ah battery pack
2S2P pack that’s 7.4V 5.2Ah battery pack
Many battery packs may consist of a combination of series(S) and parallel(P) connections.
For Laptop batteries with 11.1V 4.8Ah battery pack, it commonly has three 3.7V battery cells in series (3S) to achieve a nominal 11.1 V rechargeable battery and two in parallel(2P) to boost the capacity from 2.4Ah to 4.8Ah. As you can find it will be a configuration is called 3S2P, meaning three cells in Series and two in Parallel.
When size limitation was considered, there is much more we need to consider, see below picture.
Stop here and check if you can figure them out.
and here is the answer:
very easy, don’t you?
Let’s now calculate another 11.1V 100Ah battery pack, let’s see how many cells would be needed: 11.1V/3.7V=3, so that’s 3S 100Ah/2.6Ah=38.5 so we can use 38P(98.8Ah) or 39P(101.4Ah)
people mostly will use 3S38P so that’s 114 cells in total(3*38=114)
is all clear to you now?
What If I drop the mAh rating from 2.6Ah to 2.2Ah(which is more common for type batteries), I now need 135 cells in total with 3S45P configuration to get the same total capacity of 11.1V 100Ah(actual capacity is 11.1V 99Ah).
PS: 11.1V/3.7V=3 100Ah/2.2Ah=45.5
The calculate is still on—
What if we use Lifepo4 cells(which are rated 3.2V 1.5Ah)? we would need 264 cells in total with 4S66P configuration to get the same total capacity of 11.1V 100Ah(actual capacity is 12.8V 99Ah).
PS: 11.1V/3.2V=3.5 people normally use 4S to boost voltage,
100Ah/1.5Ah=66.6
Let’s roll the ball on.
what will happen if Watt/Hour(Wh in short) are involved?
If you have, for example, 2Ah lithium ion battery cell then each of those stores 7.4Wh (3.7V*2Ah=7.4Wh) of energy and you need 136 of them (/7.4 ~ 136) for a 1kWh battery. 136 in parallel will give you a 1kWh battery with a nominal voltage of 3.7V.
If you want higher voltage, and you probably will, you have to put them in series as well. 7s is a typical minimum for a Home UPS battery. 136 cells can’t be evenly distributed over 7 packs in series, you then need 140 cells for a 7s20p setup.
All of above are just examples, there are plenty other possibilities. It would be very hard to put this into an automatic calculator which then provides meaningful results because almost all of this depends on variables the calculator doesn’t know or that have to be put in in the first place. It is easier to calculate this yourself.
When we talk about a mAh battery, we’re referring to its energy storage capacity. But what does this number actually mean in real-world usage?
mAh (milliampere-hour) measures how much charge a battery can deliver over time.
A mAh battery can theoretically supply mA for 1 hour, mA for 2 hours, or 500mA for 6 hours.
However, real-world performance depends on factors like:
✔ Battery chemistry (Li-ion vs. LiPo vs. LiFePO4)
✔ Discharge rate (higher drain = shorter runtime)
✔ Temperature conditions (cold reduces efficiency)
Key Insight:
While mAh gives a general idea of capacity, it’s not the only factor determining battery life. A high-quality mAh LiFePO4 battery from Ufine Battery, for example, will outperform a cheap lithium-ion cell in both lifespan and stability.
Many consumers confuse mAh (capacity) with watts (power). Here’s how they relate:
Watt-hours (Wh) = Voltage (V) × Amp-hours (Ah)
Most mAh lithium batteries operate at 3.7V (standard for Li-ion/LiPo)
Calculation: 3.7V × 3.0Ah = 11.1Wh
Why This Matters:
Devices are often rated in watts, not mAh.
A mAh battery can theoretically power an 11.1W device for 1 hour.
For solar applications, knowing watt-hours helps size battery banks correctly.
Conversion of Watt Hour to Amp Hour (Wh to Ah)
Pro Tip: If you need custom voltage or capacity, Ufine Battery specializes in manufacturing lithium batteries with precise specifications for unique applications.
Not all mAh rechargeable batteries are created equal. Let’s break down the three main lithium chemistries and their performance characteristics:
✔ Voltage: 3.6V – 3.7V nominal
✔ Energy Density: 200-265 Wh/kg
✔ Cycle Life: 500-1,000 cycles (to 80% capacity)
✔ Best For: Smartphones, laptops, power tools
✔ Voltage: 3.7V nominal
✔ Energy Density: 250-300 Wh/kg
✔ Cycle Life: 300-500 cycles
✔ Best For: Drones, RC vehicles, wearable devices
✔ Voltage: 3.2V nominal
✔ Energy Density: 90-120 Wh/kg
✔ Cycle Life: 2,000-5,000 cycles
✔ Best For: Solar storage, medical devices, EVs
Critical Parameters Beyond Capacity:
Peak Discharge Current (e.g., 10C = 30A for mAh)
Continuous Discharge Rating (sustained current without overheating)
Charge Temperature Range (0°C to 45°C for most Li-ion)
Discharge Temperature Range (-20°C to 60°C for premium cells)
Internal Resistance (lower = more efficient)
Self-Discharge Rate (3-5% per month for quality cells)
Protection Circuit (essential for safety in consumer devices)
Why Choose Ufine Battery?
As a leading custom lithium battery manufacturer, we produce:
High-rate mAh batteries for drones and power tools
Ultra-thin mAh LiPo cells for sleek wearable designs
High-temperature mAh variants for industrial applications
Primary Battery Vs. Rechargeable Lithium Battery
While rare, some applications require non-rechargeable mAh batteries:
Lithium Thionyl Chloride (Li-SOCl₂)
✔ Voltage: 3.6V
✔ Shelf Life: 10-15 years
✔ Best For: IoT sensors, emergency beacons
Lithium Manganese Dioxide (Li-MnO₂)
✔ Voltage: 3.0V
✔ Shelf Life: 7-10 years
✔ Best For: Digital cameras, medical implants
Key Parameters for Disposables:
Operating Voltage Curve (how voltage drops over time)
Pulse Current Capability (critical for GPS trackers)
Storage Temperature Range (-55°C to 85°C for military-grade)
Weight & Size Constraints
Safety Certifications (UN38.3, UL)
Cost Per Watt-Hour
Environmental Impact (recycling considerations)
If you want to learn more, please visit our website SINC.
The simple answer is: it depends on how much current your device consumes.
To calculate the running time, you can use a basic formula:
Battery Runtime (hours) = Battery Capacity (mAh) ÷ Device Load (mA)
Where:
For example:
But what if the device consumes different amounts at different times?
In that case, you should calculate the average current draw based on typical usage.
Let’s look at a few practical scenarios:
Quick Tip:
Always factor in efficiency losses (typically about 10–20%) because no system is 100% efficient.
So real-world runtimes might be slightly shorter than the calculation.
Adjusted formula:
Estimated Real Runtime = (Battery Capacity ÷ Device Load) × 0.8
Following our previous 400 mA example:
( ÷ 400) × 0.8 = 6.4 hours realistic usage time.
Why Is It Important?
Understanding this helps you choose the right battery for your needs — whether you want longer playtime for your drone, more backup for your GPS tracker, or enough juice for an emergency kit.
If you’re unsure about your device’s actual power consumption, it’s a smart idea to use a USB tester or a multimeter to measure it directly for the most accurate estimate.
*Accounting for voltage drop, temperature effects, and aging
Advanced Consideration:
At -20°C, a standard Li-ion’s capacity may drop 40-50%, while Ufine’s low-temperature mAh batteries maintain 80%+ capacity through advanced electrolyte formulations.
Use this step-by-step evaluation:
Measure Your Device’s:
Average current draw (in mA)
Peak current requirements
Operating voltage range
Consider Usage Patterns:
Daily runtime requirements
Recharging opportunities
Environmental conditions
Physical Constraints:
Available space for battery
Weight limitations
Shape requirements (cylindrical vs. pouch)
When to Consider Custom Solutions:
Need unusual dimensions? Ufine offers ultra-thin batteries down to 4mm thickness.
Require extreme temperature performance? Our high-temperature series operates up to 85°C.
Need higher discharge rates? We manufacture 20C+ mAh batteries for racing drones.
Voltage Compatibility
Mismatched voltage can damage devices
Some systems need precise voltage curves
Discharge Rate (C-Rating)
Standard devices: 1C (3A for mAh)
Power tools: 10C-30C required
Cycle Life Expectations
Consumer electronics: 500 cycles acceptable
Industrial applications: + cycles needed
Temperature Resilience
Standard range: 0°C to 45°C
Industrial grade: -40°C to 85°C
Safety Mechanisms
Built-in PCM/PCB protection
Venting mechanisms for pressure relief
Physical Form Factor
cylindrical (standard)
Pouch cells (custom shapes available)
Regulatory Compliance
CE, UL, UN38.3 certifications
Transportation regulations
Ufine Advantage:
We provide complete technical specifications and custom safety certifications for all our battery solutions.
Choosing a mAh battery involves far more than comparing capacity numbers. From chemistry selection to discharge characteristics and environmental resilience, every parameter impacts performance.
For applications requiring precise specifications:
Ufine Battery delivers:
Custom lithium polymer batteries in any shape
High-rate discharge cells for power-intensive applications
Extreme-temperature tolerant designs
Complete OEM/ODM battery solutions
Ready to power your innovation? Contact Ufine Battery today for your custom mAh battery solution.
Yes — as long as voltage and size match, you’ll just get longer runtime.
Not necessarily. Charging time depends more on your charger’s output and the battery’s internal design.
It could be battery age, high background power consumption, or environmental conditions like heat.
Absolutely! Ufine Battery specializes in custom lithium battery solutions, including packs for drones, medical devices, industrial sensors, and much more.
Store it at about 40–60% charge in a cool, dry place. Avoid extreme temperatures!
For more information, please visit mAh Lithium Battery.