Lipo battery serial connection

A LiPo cell has a nominal voltage of 3. For the So a four-cell 4S pack is The voltage of a Lipo battery pack is essentially going to determine how fast your vehicle is going to go. So if you have a brushless motor with a rating of 3,kV, that motor will spin 3, RPM for every volt you apply to it.

On a 3S, it will spin a whopping 38, RPM. When you select lipo battery, you need to know your motor of rc model, Voltage has an impact on motor, and motor influence the speed.

The higher voltage is, the higher power P of the motor is, and here is the formula:. As you know, the voltage influence the power of the motor of battery, and the power has an impact on the RPM of the motor, that means speed. So in some racing, pilots need the batteries are of high voltage to meet the needs of their rc model to get a high burst. The mAh on the picture means the capacity of the lipo battery.

Capacity is used to measure how much power a battery can hold. Milliamp also can be converted to amps A , here is the conversion:. Generally, capacity can determines how long you can run before you have to recharge.

A larger capacity pack may give you longer flight times but being heavier it will adversely affect performance. Because high speed means you need more power to drive your plane or others, so your power lost quickly.

Discharge Rate "C" Rating is simply how fast a battery can be discharged safely. From the theoretical stand point, if you discharge you battery at a mAh, so the mAh of battery pack can be exhausted in half an hour. From above the calculation, draw battery at Sometime, you would be required to get a battery of high discharging rate, usually in a race, such as FPV racing, you must in a high speed and win a race.

So, you know, why so many pilots attach such a great importance into the high discharge rate. And it may more expensive than the lower one. In order to get the best flight or running time and performance it important to know how to go about choosing the best Lipo battery. Like most components on a drone or car, they are related to other components, and the battery is no exception. The correct battery mainly depends on the size of your drone or car, and the type and number of motors you use.

In this guide we will discuss how to ensure your battery will work properly with your drone or car system before you buy it. To get the longest flight or running times you should use the largest battery in terms of capacity that you possibly can but still keep within the maximum takeoff weight of your drone.

The other thing to take into account is the physical size of the battery, as depending on what drone or car you are using you will only need be able to fit a battery of a certain size. Probably the most important, but often overlooked factor to is the check the battery discharge C rating is the optimum for your drone or car.

Using a discharge rate C rating that is too low, can result in your battery being damaged, and your drone or car under-performing the battery cant release current fast enough to power your motors properly. Since higher C rating batteries are heavier, if the battery you are using has a C rating that is too high, you will just be carrying extra weight around that you dont need, ultimately reducing the running time.

In order to know what the total current draw of your drone system is, we cab calculated it based on this simple formula:. For a example, we have a mAh 3 cell Lipo battery with a 10C rating. To find the maximum continuous amp draw, we first convert the mAh to 5. As choosing the battery is often the last step to building your own drone, we will already know what motors and ESC we are using.

Since the motors will draw the most amount of energy from your battery we can base our calculation around this. There is no fixed C rating that you will need to use as the maximum current output of a battery depends on the capacity and C rating.

Typically the smaller the capacity of a battery, the higher the C rating needs to be, this is why for many high capacity multi-rotor batteries you will find very low C ratings in the range of C. Now that you know the required current draw from your battery, the capacity and C rating can be found. Our frame, electronics and motors weight come to 1. That leaves g that we can use for the battery. So you should try to find the highest capacity LiPo that you can find that weights less than this.

The battery voltage, or cell count is another important decision that you will need to make. Higher voltage batteries allow your motors to produce more power, however the higher voltage batteries are heavier since they contain more cells. There is no golden rule to follow when it comes to battery voltage, but the way you can find the best voltage for your drone is to look through your motor thrust data tables and compare the efficiency.

You will find that motors are generally more efficient and powerful when using higher cell count lipos higher voltage , but some of the efficiency bonus is negated by the increase in weight and cost of the battery. So depending on how many motors you are using you will need to choose what is best for your current setup.

Some motors will only support a specific cell count lipo, or a specific range of voltages which might make the decision easier. Soldering battery connectors can be a real pain, so it is a good idea to try find a battery connector that you like, and stick to it. That allows you to swap batteries easily, and if you decide to build another drone in the future you can use the same batteries. The number of batteries you decide to use on your drone does not ultimately make much difference as there are pros and cons of using more batteries.

Firstly using more batteries has an added layer of safety as if one battery should fail, you still have another that you can use to quickly land. Also if you have the flexibility of replacing one battery if one of them gets older than the other. Charging time can be reduced if you have two chargers as each one can charge at the same time. However using two batteries can be more complex to mount and wire and buying two batteries can sometimes be more expensive than buying one.

So, the higher the capacity the more you can run. But big capacitance causes large batteries to be overweight. More or less, it will affect the lifespan of your device.

This energy is drawn by the motors and rotors. In LiPo batteries, we often encounter something like 20C or 30C. Or, actually the discharge rate of that LiPo battery. That means-. While buying new Lipo batteries you should know which one performs better. Also, you should know how much current is drawn by your device. Because high-rated batteries suffer less voltage drop while discharging. And, through consistent voltage supply, we enjoy the best performance in use.

Remember, you have the facility to draw more power than it discharges naturally. As it consumes power faster than before, its normal peace is disrupted.

Therefore it results in overheating issues and sometimes ends in burst into flames. Sometimes performance is equivalent to the voltage it consumes. So, while caring about the discharge rate, care should be given on the number of cells it has. Because a battery with more cells provides a higher voltage.

And, that results in higher RPM for brushless motors. The battle between 3S and 4S batteries has continued for a long time. So make sure which one to buy for yours. Well, of course. Better to use a single boost regulator to charge the LiPos in series, and use a single FET to disconnect the load.

The technique of cell balancing is maybe what you're looking for. Related: Multi-Cell Lithium battery balancing circuit explanation. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How to separately charge two LiPo batteries wired in serial? Ask Question. Asked today. Active today. Viewed 39 times. Luke Moore Luke Moore 2 2 bronze badges.

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