Power Sonic specializes in the design and manufacture of valve-regulated sealed lead acid batteries, which immobilize the sulfuric acid electrolyte in absorbent glass mats to prevent spills and allow operation in nearly any orientation. Unlike traditional flooded lead acid batteries, SLA batteries do not require the periodic addition of distilled water, virtually eliminating maintenance. They also do not vent hydrogen gas in normal charging conditions, thanks to a system that recombines the gases with the electrolyte, making them safer to use in confined spaces.
Power Sonic batteries are available for a wide range of applications, including emergency lights, communications equipment, uninterrupted power supplies, emergency sump pumps, scientific equipment, power sports equipment, automobiles and solar systems. Specifications vary according to the application, with 6-volt and 12 volt batteries available and capacities that range from 0.8 to 260 amp-hours. Power Sonic SLA batteries are durable and reliable, and with proper use and charging, they can last well over 5 years before their performance begins to degrade significantly.
To maximize the lifespan of your Power Sonic batteries, here are a few things that you should avoid doing to your batteries:
#1 Overcharging Them
Nothing can ruin a rechargeable battery faster than not charging it properly. When an SLA battery is overcharged, it will begin to heat up and the electrolyte in the cells will start to decompose. This will separate the water in the electrolyte into its component gases, including highly-flammable hydrogen. As the internal pressure of the battery increases, the hydrogen will be vented out through the battery's valve. Not only will this shorten the life of the battery because the water cannot be replaced, but it will also create a fire risk, especially if the battery is located in a tightly enclosed area. As an SLA battery becomes hotter, it can accept a greater rate of charge, and if the charge rate is high enough, the battery could heat to a point that it destroys itself in a matter of hours, a process called thermal runaway.
To prevent damage to an SLA battery, it should not be charged beyond 2.45 volts per cell at an ambient temperature of 77 degrees. For a 6-volt battery with three cells, this means it should not be charged beyond about 7.35 volts, and a 12-volt battery should not be charged beyond 14.70 volts. As the temperature changes, the charge characteristics of an SLA battery change, as well. In lower temperatures, more voltage can be applied, and at higher temperatures less voltage should be applied. At 32 degrees, up to 2.60 volts per cell is acceptable, and at 104 degrees, only 2.36 volts should be applied.
To maximize the life of your battery, only use “Smart” charging equipment that senses the charge state of the battery, preferably with built-in temperature compensation. Older-style manual chargers can easily overcharge a battery if they are not monitored closely.
#2 Undercharging Them
Undercharging your batteries can also severely reduce their lifespan. When not charged completely, lead sulphate can remain on the lead plates inside the battery, coating them and preventing the electrolyte from contacting the plate properly. This process, called sulphation, reduces the battery's capacity and performance. To avoid sulphation, be sure to charge the batteries completely after discharging them.
#3 Discharging Them Deeply
SLA batteries should never be completely discharged, which will shorten their lifespan dramatically. Ideally, they should never be discharged beyond 50 percent of their total capacity, though some can withstand occasional discharges down to 20 or 25 percent of total capacity.
An SLA battery is considered full at 2.45 volts per cell and empty at 1.94 volts per cell. This means that a 12-volt battery is completely discharged at 11.64 volts, and a 50 percent charge is about 12.20 volts. A 6-volt battery is empty at 5.82 volts and halfway discharged at 6.1 volts. To measure the voltage of a battery accurately, you must wait at least one hour after charging or discharging it, and no load should be connected.
#4 Storing Them for Extended Periods
SLA batteries that are stored for long periods without recharging can suffer from a phenomenon known as self-discharge, which eventually drains the battery. This can lead to sulphation, which will damage the battery permanently. Similarly, batteries that are stored in a discharged state will also become sulphated. SLA batteries should always be stored fully charged, and they should be recharged at least every six to nine months to avoid damage.
#5 Providing Insufficient Ventilation
Under certain circumstances, such as overcharging, SLA batteries can emit flammable hydrogen gas, though not nearly as easily as flooded lead acid batteries can. To avoid the risk of fire or explosion, they should never be placed in a tightly-sealed container, and they should be kept away from sparks and open flames.
#6 Adding Water or Acid
SLA batteries are factory sealed, and require no periodic addition of water or acid, unlike flooded lead acid batteries. Doing so can cause damage to the batteries or personal injury, including burns from the corrosive sulfuric acid inside the case.
#7 Using Them in Excessive Temperatures
Placing SLA batteries in areas with excessive temperatures can dramatically reduce their lifespan. At 77 degrees, SLA batteries typically last 5 years or longer, but by increasing the temperature to 95 degrees, their lifespan is reduced to about 3 years. At lower temperatures, their lifespan increases, but their performance and usable capacity decrease.
#8 Damaging the Exterior Cases
To prevent personal injury, avoid dropping an SLA battery or otherwise damaging the case. Leaking batteries should be discarded immediately at an appropriate facility that handles hazardous waste.
#9 Mixing Batteries
When multiple batteries are connected in series or parallel, only batteries of the same type, capacity and age should be used together. Mixing batteries of different ages or specifications may reduce the performance and the overall life spans of the other batteries in the system.
By avoiding these practices, you can maximize the lifespan of your Power Sonic batteries and make sure that the devices they power perform as effectively and efficiently as possible. In addition to SLA batteries, Power Sonic also produces nickel cadmium, nickel metal hydride and lithium phosphate batteries, as well as long-life and high-discharge versions of SLA batteries.