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Sometimes we need a high current to power some heavy electrical products, so there is an option to connect two lithium-ion batteries. You can also attach more than two batteries or any other amount you want to connect per your usage. But the method is the same for connecting the lithium batteries. So, here we provided a detailed guide on How to Connect Two Lithium Ion Batteries.
The lithium-ion batteries are now commonly used in various power departments and products, including mobile phones, laptops, and even electric vehicles. But there are some products or cases in which we need to connect two or more lithium-ion batteries to obtain more power. Like in the Home UPS or solar system, we usually connect two lithium-ion batteries. you can also check How to Connect two lithium batteries Or How to connect lithium batteries in series
How to Connect Two Lithium Ion Batteries
There are two options to connect the lithium-ion batteries; one is parallel, and the other is a series method, but the most commonly used method to connect the lithium-ion batteries is a parallel method.
Can Lithium-Ion Batteries Be Connected In Parallel?
The lithium-ion batteries can be connected parallel if you need a higher current to power the heavy electric gadgets, especially in the solar system and the home UPS system. The interesting thing to know about this situation is that the voltage will remain the same, and the condition for connecting the batteries in a parallel way is that both batteries should have the same voltage.
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Another important thing you have to keep in mind while connecting the batteries in a parallel way is to always connect the negative terminal of the battery with the negative terminal and the same in the positive terminal.
How Do Lithium Batteries Connect In Parallel?
Don’t Connect Different Chemistries Battery
We know that all the batteries are based on different chemistries, and the manufacturers make the batteries according to the need of other products; the batteries used for the UPS system are extra compared to those made for mobile phones.
In the market, there are many types of lithium-ion batteries available, and people buy the batteries according to the need of their purpose. So for connecting two lithium-ion batteries, you have to, but the batteries have the same functions, like their chemistry or the working procedure will be the same. This way, you can prevent yourself and the batteries from any danger.
Like you can never connect the lithium iron phosphate batteries to the simple lithium-ion batteries; this can cause power imbalance due to their chemical compositions.
Same voltage
Another essential condition for connecting the lithium-ion batteries is that the batteries have the same voltage. For example, if you have a battery that is producing 3V, then the other battery must have 3V. If you are connecting two polymer cells, make sure that both partitions have the exact specifications; otherwise, it will be risky.
It would help if you used the same voltage because, in this way, you can use the product that you will power with two lithium-ion batteries to work smoothly.
Charge Them Up
Now the next step you need to perform is to charge the batteries so that their charging becomes the same and you can easily connect them without facing any difficulty. The professionals say that setting the batteries with the same charger is better.
Check the Open Circuit Voltage
Many people think connecting two or more lithium-ion batteries is very easy, but it is not as easy a procedure as you feel. There are many small things that you have to check, and one of them is the Open circuit voltage.
The Open Circuit Voltage between each battery should not have greater than 0.2 voltages, and for this, don’t connect the batteries after charging; make your batteries accessible for 8 hours.
Buy the Right Connecting Cables
The cables play an important role in connecting two lithium-ion batteries, ensuring the wires have the correct size. The lines should have the capacity to carry the required current; otherwise, using low-quality cables can damage your battery and your product’s power.
While selecting the cables, you have to choose lines that have a sufficient length, so you don’t face any difficulty connecting the batteries; place them together, and they don’t have a considerable distance.
Check the Main System Cables
The main cables are usually connected to the battery bank. The purpose of these cables is to balance the batteries while charging the batteries and when you are going to power any product with the help of these batteries.
So you have to ensure that the main cables and the cables used for connecting the batteries can easily pass the current production by the batteries, which means that if you need to carry a higher current, then always cables should also have the ability to do this.
Use An Isolation Fuse
There is no report of any problem similarly connecting the lithium-ion batteries, but for extra safety, you should always use an isolation fuse. It is most helpful when connecting higher voltage cells or batteries. In simple words, you can say that it is a safety precaution.
Connect The Batteries
Now finally, you have to connect the batteries in a parallel way; keep in your mind that you have to connect the positive terminal of the battery to the positive and the negative terminal of the battery to the negative; in this, you can connect the batteries as many as you want.
After connecting the batteries, you must connect the positive terminal of the first battery and the negative terminal of the last battery to the system.
Avoid 100% Discharge
Avoid 100% Discharge
After connecting the batteries, you must charge the whole system, not only one battery, so you must avoid 100% discharge. It will help not only lithium-ion batteries but also the system that you have powered by the connection of the lithium-ion batteries. For this purpose, you can use a battery monitor that shows the battery charging percentage; now, most batteries have the latest battery management system that tells you about battery discharging.