Radio control (RC) cars and other devices contain a nickel cadmium (NiCad) or nickel metal hydride (NiMH) rechargeable battery pack that is long lasting and inexpensive. The battery pack uses a standalone recharging unit that is sold separately and available at hobby and electronic shops. But like other components, you need to properly charge your RC batteries to keep them from developing a “memory effect” and dying prematurely.
Preventing “Memory Effect”
Each time you charge your RC device's NiCad battery, the battery remembers the last time it was charged as well as how long it took to recharge. Over time, the battery charges only to the amount of discharge. This is known as the memory effect. (This is not an issue with NiMH batteries.) To prevent this from happening, fully discharge your RC device's battery by using the device or leaving it on until the battery dies. Then connect the battery to its charger.
Peak Detection Chargers
When recharging your RC device's battery, use a peak detection charger instead of a timer charger. The chargers automatically stop the charging process when your RC battery is fully charged. Peak detection chargers keep your battery from overheating and overcharging, which can lead to the battery exploding. Timer chargers require you to manually set how long to charge your RC battery. A wrong setting can lead to the battery not charging properly -- under- or overcharging.
NiCad & NiMH Charging Issues
When charging an NiCad battery with a peak detection charger, make sure the charger is for NiCad batteries and not NiMH batteries. Using the wrong charger type can damage your RC battery. Consult your peak detection charger's manual for the type of batteries it can recharge.
Set your RC battery's charger to “3.5 Amps.” This is a consistent charging rate that doesn't provide too much or too little voltage to your RC battery.
Do not charge a warm or hot battery; let the battery cool first before attaching it to a charger. Charging a hot or warm battery can lead to an explosion. Do not use the same battery in your RC device more than once a day. This can lead to the battery becoming too hot and developing a memory effect, especially if you haven't fully discharged the battery. Do not store your RC battery in a hot or humid area. Heat and moisture can destroy the battery.
When charging your RC battery with a peak detection charger, it may not shut off automatically when your RC battery is fully charged. Touch the battery's case periodically to see how warm the battery is. Turn off and disconnect the charger when the battery is becoming too warm.
When connecting the charger to your RC battery, do not cross the charger's wires and touch the positive “+” and negative “-” terminals. This will cause a short and destroy your battery. When connecting the wires, connect one wire at a time and look closely at the wording on your battery's casing and the charger.