En| 中文    

Welcome to Shenzhen Doublepow Electronics Technology CO., LTD

Message Board  | Contact us    

24 service hotline

Industry news Company news
The difference between batteries in series and parallel
Time:2022-03-23 15:04:10        Hits:【 】second

How to properly connect batteries in series and parallel may sound simple enough, but by following a few simple rules, unnecessary problems can be avoided.

In a battery pack, multiple batteries are connected in series to obtain the required operating voltage. If what is needed is higher capacity and higher current, then the batteries should be connected in parallel. There are also some battery packs that combine the two methods of series and parallel. A laptop battery might consist of four 3.6V lithium-ion batteries connected in series for a total voltage of 14.4V; then two sets of batteries connected in series are connected in parallel, so that the total power of the battery pack can be Increased from 2000mAh to 4000mAh. This connection method is called "four-series-two-parallel", which means: connect two battery packs connected in series by four batteries in parallel.

A single battery is typically used in watches, back-up memory, and cellular phones. The nominal voltage of a nickel-based battery is 1.2V, the alkaline battery is 1.5V, the silver oxide battery is 1.6V, the lead-acid battery is 2V, the lithium battery is 3V, and the lithium-ion battery has a nominal voltage of 3.6 V. Use Lithium Ion Polymer and other types of Lithium batteries, which are generally rated at 3.7V. If you want to get an uncommon voltage like 11.1V, you have to connect three of these batteries in series. With the development of modern microelectronics technology, we can already use a 3.6V lithium-ion battery to power cellular phones and low-power portable communication products. Mercury batteries, which were widely used in illuminometers in the 1960s, have now been completely withdrawn from the market due to environmental concerns.

Nickel-based batteries have a nominal voltage of 1.2V or 1.25V. There is no difference between them other than market preference. Most commercial batteries, the voltage of each battery is 1.2V; industrial batteries, batteries, the voltage of each battery is still 1.25V.

in parallel

To get more power, two or more batteries can be connected in parallel. In addition to connecting the batteries in parallel, another option is to use larger batteries. Due to the limitations of the batteries that can be used, this method is not suitable for all situations. In addition, large-sized batteries are not suitable for the form factor required for dedicated batteries. Most chemical batteries can be used in parallel, and lithium-ion batteries work best in parallel. A battery pack consisting of four cells in parallel keeps the voltage at 1.2V while quadrupling the current and runtime.

Example of a battery pack In a parallel battery circuit, the effect of high impedance or "open" cells is less than that of a battery in series, however, paralleling battery packs reduces load capacity and reduces run time. It's like an engine that only starts three cylinders. A short circuit can cause even more damage because, in the event of a short circuit, a failed battery can quickly drain the other batteries and cause a fire.


Portable devices that require high power are typically powered by a battery pack of two or more cells connected in series. If a high voltage battery is used, the conductors and switches can be made small in size. Mid-priced industrial power tools generally use batteries with a voltage of 12V to 19.2V; while advanced power tools use batteries with a voltage of 24V to 36V for more power. The auto industry eventually increased the starter's ignition cell voltage from 12V (actually 14V) to 36V, or even 42V. These battery packs consisted of 18 lead-acid batteries connected in series. In early hybrid cars, the battery pack used to power the car was 148V. The battery pack used in newer models has a voltage as high as 450V to 500V, and most of them are nickel-based chemistry batteries. A nickel metal hydride battery pack with a voltage of 480V is composed of 400 nickel metal hydride batteries connected in series. Some hybrid vehicles have also been tested with lead-acid batteries.

A 42V car battery is expensive, and it will arc more on the switch than a 12V battery. Another problem with using high-voltage battery packs is the possibility of encountering the failure of one of the cells in the pack. It's like a chain, the more batteries connected in series, the higher the chance of this happening. As long as there is a problem with one battery, its voltage will drop. By the end, a "disconnected" battery may interrupt the delivery of current. Replacing a "bad" battery is also not an easy task, since old and new batteries are not compatible with each other. Generally speaking, the capacity of new batteries is much higher than that of old batteries.

(The articles published on this website are all from the Internet and do not represent the views of this website. If there is any infringement, please contact to delete)

Copyright © 2022 Shenzhen Doublepow Electronics Technology CO., LTD         粤ICP备18008903号-1

Leaving a message.

After receiving the message, I will contact you