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How to Connect Lithium Batteries in Series and Parallel Correctly
XINWEN  Addtime£º2018/12/18   Read£º72 Times¡¾ Fontsize£ºL M S ¡¿

The purpose of lithium battery parallel connection is to increase capacity. Therefore, lithium battery parallel charging has different design characteristics compared with single lithium battery, mainly reflected in the consistency of charging current design and parallel battery.

 

 

The characteristics of parallel lithium batteries are as follows: the voltage is constant, the capacity of batteries is added together, the internal resistance is reduced, and the power supply time is prolonged. The core content of parallel charging is the magnitude and function of parallel current. According to the parallel theory, the trunk current equals the sum of the branch currents. Therefore, in order to achieve the same charging efficiency as a single battery, the n-section parallel lithium batteries that have been combined as batteries should have the same charging current as the n-section lithium batteries. Under the formula of Ohm's law: I=U/R, this design is reasonable. However, the internal resistance of parallel batteries will also change. According to the formula of parallel internal resistance, the total internal resistance of two parallel lithium batteries is equal to the ratio of the product of internal resistance of two batteries to the sum of their internal resistance, and the parallel resistance will decrease with the increase of the number of parallel batteries. Therefore, the efficiency of parallel charging of lithium batteries can be realized on the basis that the current of lithium batteries in parallel is less than the sum of the current of N lithium batteries in parallel.

 

 

In parallel connection of lithium batteries, attention should be paid to the consistency of batteries, because the poor consistency of parallel lithium batteries will lead to the phenomenon of non-charging or over-charging during the charging process, thus destroying the battery structure and affecting the life of the battery group. Therefore, when selecting parallel batteries, lithium batteries of different brands, different capacities and different degrees of old and new should be avoided. The inherent requirements for battery consistency are: the voltage difference of lithium batteries is less than 10 mV, the internal resistance difference is less than 5 m, and the capacity difference is less than 20 mA.

 

 

In fact, after parallel connection of lithium batteries, there will be a charge protection chip to protect lithium batteries. When making parallel lithium batteries, lithium batteries manufacturers have fully considered the characteristics of changes after parallel connection of lithium batteries. They also design current and select batteries according to the above requirements. Therefore, users need to charge in accordance with the instructions of parallel lithium batteries in order to avoid them. Avoid possible damage to batteries caused by incorrect charging.

 

 

Battery series voltage is equal to the total battery voltage in series. Increase the voltage. The bulb is in series. A switch can control all the bulbs connected in series on a single line.

 

 

The output voltage can be increased when the cells are connected in series. What are the characteristics of the bulbs connected in series? The sum of the two voltages of each bulb is the total voltage of the circuit.

 

 

When the batteries are connected in series, the voltage is added up and the currents are equal, thus increasing the voltage; if the batteries are parallel, the voltage will remain unchanged (provided that the batteries with the same voltage can be connected in parallel, otherwise the high voltage will charge the low voltage, and if the difference is too large, it may be dangerous). The current equals the sum of the batteries, which can often be considered as increasing the capacity of the batteries and providing more current. ¡£

 

 

Voltage increases, capacity remains unchanged.

 

 

The difference between series and parallel batteries:

 

 

Batteries in series:

 

 

It refers to the connection between the head and the tail of the battery. That is, the positive pole of the first battery is connected with the negative pole of the second battery, and the positive pole of the second battery is connected with the negative pole of the third battery by analogy.

 

 

Series voltage equals the sum of battery voltage and current equals the current flowing through each battery.

 

 

Damage to one section of the battery pack can cause the whole battery pack to be unusable or the voltage to drop.

 

 

Series connection can increase the total voltage.

 

 

Batteries in parallel:

 

 

It refers to the connection between the head and the tail of the battery. That is, the positive poles of all batteries are connected, and the negative poles of all batteries are connected.

 

 

The parallel voltage is equal to the voltage of a single battery and the current is equal to the sum of the current of the battery.

 

 

Although the batteries'endurance is enhanced, the damage caused by short circuit current is more serious.

 

 

Parallel connection can increase the total current.

 

 

1. When the battery is parallel, the voltage is equal everywhere, that is, Ua = Ub = Uc = Uo; the current is the sum of the current of each battery, that is Io = Ia + Ib + Ic. (See Figure 1, Parallel Circuit of Batteries)

 

 

Batteries in parallel are suitable for situations where the voltage is constant and the current needs to be increased.

 

 

2. When the battery is in series, the current is equal everywhere, i.e. Io=Ia=Ib=Ic; the voltage is the sum of the voltage of each battery, i.e. Uo=Ua+Ub+Uc. (See the Series Circuit of the Battery in Figure 2)

 

 

Batteries in series are suitable for situations where the current is constant and the voltage needs to be increased.

 

 

Whether in series or in parallel, the output power of the battery increases.

 

 

Parallel connection: Several batteries, positive and positive, negative and negative, are connected side by side. The voltage remains unchanged, the capacity increases, and the corresponding current increases. Series: Several batteries are connected in series, that is, positive and negative, negative in the first section and positive in the second section, and so on. Voltage increases, capacity remains unchanged. That is to say, if connected in series, the electromotive force is the sum of the electromotive force of two batteries. If connected in parallel, the voltage they provide to the appliances is as large as the electromotive force of only one battery. I hope my answer can help you! I'm also learning this part of the knowledge. It's difficult.

 

 

When connected in series, the voltage is the sum of two battery voltages. When connected in parallel, the voltage is equal to that of the two batteries.

 

 

Increase voltage in series and capacity in parallel. For example, if you have two batteries of 1.5 volts and 2000 milliamperes, you will get a battery of 3 volts and 2000 milliamperes in series and a battery of 1.5 volts and 4000 milliamperes in parallel.

 

 

1. When the battery is parallel, the voltage is equal everywhere, that is, Ua = Ub = Uc = Uo; the current is the sum of the current of each battery, that is Io = Ia + Ib + Ic. (See Figure 1, Parallel Circuit of Batteries)

 

 

Batteries in parallel are suitable for situations where the voltage is constant and the current needs to be increased.

 

 

2. When the batteries are in series, the current is equal everywhere, i.e. Io=Ia=Ib=Ic; the voltage is the sum of the voltages of the batteries, i.e.


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