What Is a LiPo Battery?
Lithium polymer cells, LiPo for short, are batteries that use polymer electrolytes rather than the traditional liquid electrolyte. LiPo batteries have four times the energy density of nickel-cadmium batteries. This means that they can store more energy in lighter weights, and since they can be forged in nearly every shape, LiPo batteries have become popular in the DIY community.
Aside from their light weight, LiPo batteries are also rechargeable, which makes them reusable and sustainable. To charge a LiPo battery, you’re going to need a LiPo charger.
There are a variety of LiPo battery chargers. However, if you’ve got good-quality LiPo batteries, then you should definitely invest in a LiPo balance charger. A balance charger offers more than just simple charging: it also has the ability to balance charge your LiPo battery, which is crucial to the battery’s health.
What Is a LiPo Balance Charger?
A LiPo balance charger is a handy piece of hardware that allows you to fully tend to your battery’s charging needs. The most important thing that this charger offers, which also gives it its name, is balance charging.
A balance charger has a balance connector slot in addition to the main power connectors. This allows the charger to read the voltage for each cell and adjust its charging accordingly so that all cells are charged evenly, with no voltage differences. This will prolong the lifespan of your battery.
In this article, we’re going to use an iMAX B6AC LiPo balance charger.
Charging a LiPo Battery
Before charging your LiPo battery, you should first get to know your battery and its specifications. This is important as you have to select the correct setting on your balance charger.
Traditionally, each LiPo cell is 3.7 volts with a maximum voltage of 4.2V. For a three-cell LiPo battery, the voltage will be 3.7V x 3 = 11.1V and the maximum voltage will be 4.2 x 3 = 12.6V. Your battery should not exceed its maximum voltage. Helpfully, balance chargers read the voltage and notify you when your battery is at its full voltage.
LiPo balance chargers can achieve a variety of charging methods for different purposes. Let’s see what your balance charger is capable of.
Charging
Plain, basic charging. This will simply charge the battery with a higher current and without regard to the cell voltages, so you don’t need to connect the balance connector.
The issue with basic charging is that although the voltage of the battery might seem normal, the cells may not be equally charged. One cell may be overcharged while the others are undercharged.
However, if you’re in a hurry or have a single cell LiPo battery to charge, this method is reasonable. To charge your LiPo battery:
Insert the male side of the power connectors into the balance charger’s power slots. Remember that black goes to negative, and red goes to positive. Connect the crocodile clamps of the power connectors to your battery. Pay extra attention that you connect red to red and black to black. Turn on the balance charger and go to the Charge setting. This is usually the first setting. Select your battery type. In this case, we’re using a three-cell LiPo battery. Check the connections once more, then press the Start button and confirm. The balance charger will now start charging your battery!
Balance Charging
If you’re not in a hurry and care about your battery’s well-being, then balance charging is the way to go. With balance charging, the voltage of each cell becomes readable for the charger through the balance connector. This lets the charger balance the cells, which will increase the lifespan of your battery in the long run.
To balance charge your LiPo battery:
Connect the power connectors to the balance charger’s power slots. Remember that black goes to negative, and red goes to positive. Connect the clamps of the power connectors to your battery. Make sure that you connect red to red and black to black. Insert the balance connector of your battery to the designated slot in the balance charger. Turn on the balance charger and go to the Balance Charge setting. This is usually the second setting. Select your battery type. Check the connections and once you’re sure, press the Start button and then confirm. The balance charger will now charge and balance your battery cells.
Storage Charging
If you plan on not using your LiPo battery for a while, it’s a good idea to storage charge it before you store it.
LiPo batteries, like most batteries, slowly discharge on their own. If you store a discharged battery for a long time, the battery might discharge below its safe range and then become dead.
On the other hand, if you fully charge a battery and leave it unused, the cells will unbalance, which can harm your battery and reduce its lifespan and functionality. Using the storage charge method will charge or discharge the battery to an appropriate value; not fully discharged nor fully charged.
To storage charge your battery:
Connect the power connectors to the balance charger. Black goes to negative, and red goes to positive. Connect the crocodile clamps of the power connectors to your battery. Red to red and black to black. Turn on the balance charger and go to the Storage Charge setting. Select your battery type. Check the connections, then press Start and confirm. The balance charger will discharge or charge your battery to the proper storing voltage.
Once you have storage charged your battery, it’s best to store it in somewhere cool like a fridge. Make sure to put it in a bag and wrap it to prevent moisture from getting in.
Discharging a LiPo Battery
In some scenarios, like trying to test the capacity of your LiPo battery, you might need to fully discharge it. You can safely do this using your balance charger.
Connect the black power connector to the negative slot on the balance charger, and the red power connector to the positive. Connect the crocodile clamps of the power connector to your battery. Red to red and black to black. Turn on the balance charger and navigate to the Discharge setting. Select your battery type. Check the connections, press Start, and then confirm. The balance charger will now discharge your battery.
Don’t leave your battery discharged for a long time. The battery automatically discharges at a slow rate and if this happens to an already discharged battery, the voltage might drop to the dead zone and kill your battery.
Safely Charging and Discharging
A balance charger is a must-have if you own a multicell LiPo battery. This tool allows you to charge and discharge your battery accordingly without damaging it. Dead and damaged batteries, however, are not completely worthless. You can still use them in your DIY projects!