What does balancing really mean? Balancing means equalizing the voltages between the cells of a LiPo pack. You can balance before, during or after charging the pack.
So why would you balance a LiPo pack? Balancing a LiPo pack improves performance. It will also improve the life of the pack and increase the safety. This happens because balancing prevents one of the cells from going below the safe range, while one or more of the others is fine. Most Lipos have a safe range somewhere between 3 to 3.25 volts. RC cars that are equiped to handle Lipos have a low voltage cutoff programmed into their ESC’s. This feature makes the car or truck LiPo safe. But if the packs cells are out of balance the ESC is going see a voltage of 6 volts and continue to draw power. The low cell could be damaged during this time because it is lower than the 3 volt safety range creating a safety concern.
So, when do I balance? This definitely depends on how often the pack is used. I race or practice almost every weekend, so I balance mine after charging at least once a month. There are manufacturers that claim that their packs do not need balancing, but I really do not feel this is true, so for safety reasons I would balance them anyway. New packs should be balanced on first use because they may have been sitting on the shelf for a long period of time and could be out of balance.
Is there any special equipment needed? For the most part all LiPo packs have a balancing plug installed. Most of the good quality peak detecting chargers have a balancing cycle, or will balance during charging. You can also purchase stand alone balancers that the plug will plug into. There are a few different styles of balancing plugs so make sure the one that you purchase is compatible with your packs.
A good quality charger that has a built in balancer is the best way to go. These chargers will use different methods of balancing. Most will use the balance plug which is preferred. There are some that just use the balance plug to check voltages, but this method is not nearly so effective. On these types of chargers; when they detect an over voltage situation they will stop charging. You are now aware of the situation, but the pack is still out of balance. The better chargers will detect which cell is over and it will slow down the charge rate. The charge rate will remain the same on the other cells allowing them to “catch up”.
If you do want to use a stand alone balancer; these devices work by using the balance plug to slowly discharge the high cells to match the lower ones.
So what does all this mean? Balancing will not hurt you packs in any way. It will increase the life of your investment. I recommend purchasing a charger that has a built in balancer. Use it every time you charge. I run a separate balance cycle about once a month just as an additional measure. This will allow you to maintain a safely balanced pack that will perform just as you expect it to.
