UNDERSTANDING THE DIFFERENCES BETWEEN CHEMISTRIES OF DEEP-CYCLE GOLF CAR BATTERIES
While some users might think the types of batteries in their golf cars haven’t changed in decades, the truth is that there have been many improvements. Many of these make deep-cycle batteries deliver longer cycle-life, provide more capacity, and cycle-up to full rated capacity faster than previous designs.
With three basic battery chemistries available, it can be challenging to decide which is the best type of battery for your particular golf car and application. Previously, there were two main types of deep-cycle batteries; flooded lead-acid (FLA) and absorbed glass mat (AGM). Today, lithium-ion batteries have also entered the market. This brings even more questions and a multitude of products from which to choose. Since all three provide certain advantages and disadvantages in a wide variety of applications, it is important to understand how they can be optimized for a given application.
Flooded lead-acid batteries are still the most popular in most applications. Updates to this over 150-year-old technology include improved positive electrodes using tetrabasic lead sulfate crystals that are formed in a more uniform pattern. This increases initial capacity, provides faster cycle-up to peak capacity, and enhances cycle-life.
The basic design of an FLA battery has the electrodes submerged in a liquid aqueous electrolyte. Over time, water in the electrolyte will be lost from electrolysis during charging and must be replaced. This requires regular maintenance in the form of water replacement, cleaning, and re-tightening terminals. Maintenance also includes keeping the batteries fully charged to prevent sulfation and to avoid freezing in cold weather. The advantages of FLA batteries are that they are safe, reliable, low-cost, and offer a wide range of capacities. They are also nearly 100-percent recyclable – the highest in the industry.
AGM batteries have the electrolyte absorbed in special glass mats that surround the battery’s electrodes, rather than being submerged in a liquid electrolyte. This allows the battery to be sealed with a special one-way valve to control gassing and water loss and eliminates the need to add water (no maintenance). This also prevents electrolyte leakage in even the most extreme conditions. AGM batteries are more expensive than FLA batteries but they are an excellent option for applications with difficult-to-access battery compartments. AGM design advancements in positive electrode corrosion resistance and carbon-enhanced negative active materials have improved their charge acceptance in a partial state of charge applications and increased cycle life over previous models. AGM batteries are also nearly 100-percent recyclable.
Lithium-ion batteries are newer to the market, and while they started at a much higher cost, ongoing cost reductions and improvements in battery management systems (BMS) required to use them in golf cars have made them a more appealing option for some owners. Deep-cycle lithium-ion batteries have increased the average cycle-life from 2,000 to 5,000 cycles and can be discharged beyond 50-percent DOD without reducing cycle-life. The latest designs, like U.S. Battery’s ESSENTIAL Li deep-cycle golf car battery, feature a built-in BMS. The advantage is that additional electronics or special chargers are no longer needed in most applications. Lithium batteries do not require special maintenance. Some models enable users to monitor the battery’s state of charge from an LCD screen or from a mobile app that connects to the battery via Bluetooth. These batteries come at a higher initial cost than FLA and AGM chemistries and currently, lithium-ion batteries are not easily recyclable and must be disposed of properly.
