Gel cell batteries, found in boats, power wheelchairs, and small-engine transports like golf carts, contain electrolytes suspended in a silica additive that sets and stiffens, and are hermetically sealed. These non-spillable, deep-cycle cells allow safe operation under heavy pressure and shock, converting oxygen and hydrogen from the charging process back into water. They are sealed so they cannot be refilled with electrolyte; as such, it's vital to control the rate of charge in order to preserve the life of the battery. While most battery chargers, including universal gel battery chargers, can work with most types of batteries, only a dedicated gel battery charger can be used for recharging gel batteries.
These batteries can operate even when their case is cracked. The interior thickening agent keeps the electrolyte in place. Gel cells must use lower charge voltage than flooded cells, requiring adjustment of the set points on the equipment. In addition, gel cells dispel charge at a higher rate. These high performers exhibit greater sensitivity to voltage overcharges, and can diminish or fail quickly with improper charging.
A good gel battery charger must therefore take the guesswork out of accurate and complete deep cycle recharging. A smart charger is usually the recommended type of gel battery charger. This type of charger can allow for gel's slower, longer charging requirements. It charges based on computer algorithms by collecting information from the cell, and modulating voltage and charge current accordingly. These chargers can be left plugged in without overcharging or damaging the battery.
Chargers may permit two types of charging: fast and float charging. Fast, or cyclic charging, requires monitoring of voltage, temperature, and current. It's necessary to switch off once the voltage reaches the desired level. Float charging, also known as standby service, provides a constant voltage and temperature, and allows the battery to moderate its own voltage level.
Assess your needs when it comes to charging times; faster charges require increased amps from a gel battery charger. Calculate the battery's amp hour rating divided by charger rating, and add about 10% extra time to maximize the charge. If a dead boat battery is rated at 100 amp hours, a 10-amp charger requires about 11 hours for a full recharge. Confirm that the charger meets your technical needs, and check reviews to learn about customer experiences with the charger, to ascertain how reliable and durable it is in operation.
Other considerations include whether you need to charge multiple batteries banked together, the input voltage of any foreign countries you may need to charge in, or whether you need a charger that can double as an RV power supply. Waterproofing and weatherproofing increase versatility for a charger. Careful maintenance of your gel battery charger and batteries will help ensure trouble-free operation when you may need it most.