Overcharging of the batteries will result in some cases. This can cause even an intelligent battery charger to not sense that the batteries are actually already fully charged, and continue charging. The problem is, the magnitude of “delta-V” can become very small or even non-existent if (very) high capacity rechargeable batteries are recharged. Such chargers are often labeled as a ΔV, “delta-V,” or sometimes “delta peak”, charger, indicating that they monitor the voltage change. After that, the voltage decreases, which indicates to an intelligent charger that the battery is fully charged. An intelligent charger may monitor the battery’s voltage, temperature or time under charge to determine the optimum charge current and to terminate charging.įor Ni-Cd and NiMH batteries, the voltage across the battery increases slowly during the charging process, until the battery is fully charged. The output current of a smart charger depends upon the battery’s state. “dumb” batteries, which lack any internal electronic circuitry.Some smart chargers are designed to charge: A smart charger is defined as a charger that can respond to the condition of a battery, and modify its charging actions accordingly. A smart battery generally requires a smart charger it can communicate with (see Smart Battery Data). A smart battery is generally defined as one containing some sort of electronic device or “chip” that can communicate with a smart charger about battery characteristics and condition. As long as the ripple current is not excessive (more than 3 to 4 times the battery manufacturer-recommended level), the expected life of a ripple-charged VRLA battery will be within 3% of the life of a constant DC-charged battery.Ī “smart charger” should not be confused with a “smart battery”. The maximum ripple current for a typical 12 V 100 Ah VRLA lead-acid battery is 5 amps. Generally, when the ripple current is within a battery’s manufacturer recommended level, the ripple voltage will also be well within the recommended level. Simple AC-powered battery chargers usually have much higher ripple current and ripple voltage than other kinds of battery chargers because they are inexpensively designed and built.

These chargers also vary in that they can supply either a constant voltage or a constant current, to the battery. Even so, many batteries left on a simple charger for too long will be weakened or destroyed due to over-charging. Typically, a carefully designed simple charger takes longer to charge a battery because it is set to use a lower charging rate to prevent damage. This simplicity means that a simple charger is inexpensive, but there are tradeoffs. A simple charger typically does not alter its output based on charging time or the charge on the battery. A simple charger works by supplying a constant DC or pulsed DC power source to a battery being charged.

Nicd battery pulse charge specs