Lipo Batteries C Rating Meaning-Definition and Capability

LiPO batteries are some of the most used batteries in portable electronics devices like smartphones and Laptops. Like any other battery technology, LiPO batteries also degrade with time and there are several factors that affect the performance and overall battery life of LiPO batteries. One of the major factors that affect the performance and how you charge your battery to ensure it lasts longer is C rating. 

While manufacturing an electronics device, one of the factors considered while choosing a battery is the battery's c rating. In case you want to replace the battery for any of your electronics devices, the c rating is very important especially if the battery is not one recommended by the manufacturer of your device.

In this article, I am going to share with you everything you need to know about c rating and its applicability to a daily user in real life. 

3.2V 20A Low Temp LiFePO4 Battery Cell -40℃ 3C discharge capacity≥70% Charging temperature：-20~45℃ Discharging temperature: -40~+55℃ pass acupuncture test -40℃ maximum discharge rate：3C

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What does C rating in LiPO battery mean?

C rating in LiPO batteries determines the maximum amount of energy that can be drawn from the battery at a time. It is from the c rating that you will determine the maximum amount of current that can be drawn from the battery without causing any significant issues to the battery. The current that you are supposed to draw from the battery depends on its c rating and the capacity of the battery. 

The formula for calculating maximum discharge current is as shown below.

Maximum discharge current = C rating x battery capacity

For example, if a LiPO battery has a capacity of 3000mah and a c rating of 2C. The maximum amount of current will be calculated as follows; 

Maximum discharge current =2x3000=6A

This implies that any device that is meant to use such a battery should not draw current that is beyond 6A. In a situation where the device uses more current than the recommended maximum discharge current, the battery will start to overheat. This reduces the life of the battery in the long run and may also cause immediate damages to the battery and in the worst-case scenario the device itself. 

C rating is also used to determine the maximum current you should use to recharge the battery. Use a higher current than the recommended may at times lead to overheating of the battery while charging it. Laptops and smartphone batteries these days have fast charging capabilities. We have some smartphone batteries in the market today that can be fast charged with current of up to 9A without causing any significant effects because they have a c rating that can accommodate such current. 

Charging such a battery with less current will make it to charge slower and there is absolutely no problem with that if you can afford to wait. 

What C rating of a LiPo battery do you need?

There is no standard c rating that is recommended for every LiPO battery. The c rating of the battery you get should entirely depend on what the manufacturer of the device recommends. Because using a battery with a wrong c rating (more so if its lower than the recommended) puts your device at risk of being damaged by the battery. Like we have seen above, there are 2 major factors that you need to consider while choosing the c rating of the battery. These include; 

1.What your device manufacturer recommends 

The manufacturer knows the minimum amount of energy needed to power up your device. It is from this that they derive the current you need and the c rating. So, manufacturers will always recommend getting batteries with a c rating that makes it possible for the device to draw the current required to power it up without causing any issues to the battery.

If your device manufacturer recommends getting a battery with 2C, you need to get one with the same rating or slightly higher but not below. Getting one that is below will most likely create some negative effects on the battery

2.The current needed by your device

The more the current needed by your device the higher the c current you need. So, getting a battery with a higher c current will make it possible for your device to draw enough current from the battery to power it up. 

What you also need to take note of is some manufacturers use the c rating value as a way of selling to you their batteries. You need to ensure you read reviews of the battery you are about to buy to see the experience of the previous customers that have used the same battery. 

Is a high C rating LiPo battery better?

The higher the battery c rating, the less the internal resistance in the battery is. This is what gives batteries with higher c ratings the ability to discharge higher amounts of current. What does this mean to the final user? This means you will be able to use the LiPO battery in your device without experiencing a lot of heating issues even if you are doing a lot of stuff on your device. 

Heat may mainly come from your device's CPU and other motherboard components but not the battery. A LiPO battery with a higher c rating also makes it possible to fast charge it with a higher power adapter. Today we have smartphone with 4000mah batteries that can be charged to full capacity within 60 or 70 minutes. This is all possible because these batteries have a higher c rating that makes it easy to fast charge the battery without experiencing any heating problems along the way. 

So, if given two options, it's always better to choose a LiPO battery with a higher c rating than one with a lower c rating. With a higher c rating, you will have the advantage of having your device to do intensive tasks without overheating and also have the capacity of charging it faster as well. 

However, fast charging is only possible with the high capacity chargers. For instance, in iPhones, you will only get the advantage of fast charging if you are using a 15W or 18W adapter. If you use the 5W adapters that are normally shipped along with the iPhones, you may end charging the phone for like 3 or 4 hours especially those with big batteries like the iPhone 11 models.