How to Charge LiPo Cells
- 1). Use only a charger designed for LiPo batteries. Do not use a charger intended for charging NiCd or NiMH batteries. Doing so will damage your LiPo battery irreversibly.
- 2). Do not "fast charge" your LiPo cells. Charge at low rates, and never charge higher than the capacity of the battery (no more than 1C maximum charge rate).
- 3). Connect the charge lead to the charger, and then connect the battery to the charge lead. Do not connect the battery to the charge lead if the latter is not connected to the charger.
Some batteries will have a red 2-pin charge connector, while other batteries will have a balancing connector. Connect the red positive lead to the corresponding red positive jack on the charger, and the same for the black negative lead and black negative jack. For those batteries with a balancing connector, you must choose an adapter lead that matches the number of cells in your battery pack. Your charger must be able to handle the exact number of cells or the battery could be charged improperly. (Some advanced chargers can auto-detect the number of cells, but they can also be wrong, so it is best to manually double-check.) - 4). Set output voltage to match nominal voltage of the entire battery pack. Because a nominal LiPo cell contains 3.7 volts, a 5-cell LiPo battery pack will have a total voltage of 18.5 volts. Setting the charger to greater than this total nominal voltage or allowing the cells to charge above 4.2 volts (or 21 volts for a 5-cell pack) could result in overcharging, permanent damage to the battery and personal injury. By the same token, do not allow the cell to discharge to lower than 3 volts (or 15 volts for a 5-cell pack) as that can also damage the cells.
- 5). Charge at Constant Current until voltage reaches 4.2 volts, then charge at Constant Voltage until the charge current reduces to 3 percent of the rated current. Follow up with a top-off charge every 20 days to counteract self-discharge and maintain the voltage at 4.2 volts.
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