Imagine getting your first hole-in-one, only to find that you must carry your golf clubs to the next hole because the golf cart batteries died out. That would certainly dampen the mood. Some golf carts are equipped with a small gasoline engine while some other types use electric motors. The latter are more eco-friendly, easier to maintain, and quieter. This is why golf carts have been used on university campuses and large facilities, not just on the golf course.
A key element is the batery used as it dictates the golf cart’smileage and top speed. Each batery has a certain lifespan depending on the typeof chemistry and confguraton used.The consumer would ideally like to have the highest lifespan possible with the lowest amount of maintenance needed. Of course, this would not come cheap,and compromises are required.It is also important to distnguish between short-term and long-term batery usage.
How much will the batery last in terms of short-term usage is translated to how many miles the golf cart can cover before recharging the batery. The long-term usage indicates how many charging-discharging cycles can the batery support before degrading and failing. To estmate the later, the electrical system and the type of bateries used need to be considered.
Golf cart electric system
To know how long golf cart batteries last, it is important to consider the electrical system that the battery is part of. The electric system is composed of an electric motor and connected to a battery pack made of battery cells in different configurations. Typical electric motors used for golf carts are rated at 36 volts or 48 volts.
In general, most electric motors would draw anywhere between 50-70 amps when running at a nominal speed of 15 miles per hour. This is however a vast approximation since there are many factors that can affect the load consumption of the engine. The type of terrain and tires used, motor efficiency, and weight carried can all affect the load used by the engine. In addition, load requirements increase on engine start-up and during acceleration compared to cruising conditions. All these factors make engine power consumption non-trivial. This is why in most cases, the battery pack used is oversized (safety factor) by about 20% to guard against conditions of very high demand.
These requirements affect the selection of the battery type. The battery should have a capacity rating sufficient to provide a large mileage for the user. It should also be able to withstand sudden surges of power demand. Additional sought-after features include the low weight of the battery packs, the ability to fast charge, and low maintenance requirements.
Excessive and sudden applications of high loads shorten the lifespan of batteries regardless of chemistries. In other words, the more erratic the driving cycle, the shorter the battery will last.
Battery types
In addition to the driving cycle and engine usage, the type of battery chemistry will dictate how long the golf cart battery will last. There are many batteries available on the market that can be used to run golf carts. The most common packs have batteries rated at 6V, 8V, and 12V. The type of pack configuration and cell used dictates the capacity rating of the pack. There are different chemistries available, most commonly: lead-acid batteries, lithium-ion batteries, and AGM lead-acid.
Lead-acid batteries
They are the cheapest and most widely used type of battery on the market. They have an expected lifespan of 2-5 years, the equivalent of 500-1200 cycles. This is dependent on usage conditions; It is not recommended to discharge below 50% of the battery capacity and never below 20% of the total capacity as it induces irreversible damage to the electrodes. Thus, the full capacity of the battery is never exploited. For the same capacity rating, lead-acid batteries would provide a shorter mileage compared to other types of batteries.
They have a lower energy density compared to other batteries. In other words, a battery pack of leadacid batteries will have a higher weight compared to the same capacity of lithium-ion batteries. This is detrimental to the performance of the golf cart’s electric system. They should be regularly maintained, most notably by adding distilled water to conserve the electrolyte level.
Lithium-ion batteries
Lithium-ion batteries are more expensive compared to lead-acid batteries but for the right reason. They have a higher energy density meaning they are lighter, they can also better handle large surges of power requirements typical of accelerating during driving and startup conditions. Lithium-ion batteries can last anywhere between 10 to 20 years depending on charging protocol, usage habits, and battery management. Another advantage is the ability to discharge almost 100% with minimal damage compared to lead acid. However, the recommend charge-discharge phase remains the 80-20% of total capacity.
Their high price is still a turn-off for small or low-grade golf carts. In addition, they are more susceptible to thermal runaway compared to lead-acid batteries due to the highly reactive chemical compounds used. Thermal runaway can arise in case of severe degradation or physical abuse, such as crashing the golf cart. It is to note however that lead-acid batteries offer no protection in case of thermal runaway while lithium-ion batteries are typically equipped with a battery management system that can protect the battery before thermal runaway onset in certain conditions.
Self-discharge can also occur as the battery degrades. This would decrease the available capacity and thus the total mileage possible on the golf cart. The process is however slow to develop with a large incubation period. On lithium-ion batteries that last 3000-5000 cycles, it should be easy to spot and change the battery pack once the degradation exceeds acceptable limits.
Deep-cycle lithium iron phosphate (LiFePO4) batteries are widely used in various applications, including golf carts. These batteries are specifically designed to provide a steady and reliable current output. The chemistry of lithium iron phosphate (LiFePO4) has been extensively researched and is among the most widely adopted lithium-ion battery chemistries. One of the key advantages of lithium iron phosphate batteries is their enhanced safety characteristics. The use of LiFePO4 chemistry significantly reduces the risk of a thermal runaway due to the inherent stability of lithium iron phosphate, assuming no direct physical damage occurred.
Deep-cycle lithium iron phosphate exhibits other desirable characteristics. They have a long cycle life, meaning they can endure a significant number of charge and discharge cycles before showing signs of degradation. In addition, they have excellent performance when it comes to high power demands. They can efficiently handle large surges of power required during acceleration or other high-demand situations commonly encountered in golf cart usage. These characteristics are particularly attractive for golf carts with high usage rates.
AGM
AGM stands for absorbed glass mat batteries. They are sealed versions of lead-acid batteries, the electrolyte (acid) is absorbed and held within a glass mat separator, which is placed between the battery plates. This design allows for a spill-proof battery, as the electrolyte is immobilized and cannot freely flow like in traditional flooded lead-acid batteries. They require less maintenance and charge up to five times faster than conventional lead-acid batteries. This type of battery can last up to seven years.However, it comes at a higher price with relatively little enhanced performance.
Conclusion
In summary, golf cart batteries dictate the performance of the golf cart, especially its mileage. It is crucial to estimate how long the golf cart battery will last for maintenance planning and considerations. Lithiumion batteries offer the best performance and longest life span compared to other common battery types in the market such as lead-acid. Their corresponding high price, however, might prove too large of an obstacle for their implementation in low-cost golf carts. Consumers rely in this case on extending leadacid battery life with proper maintenance and expect multiple changes of battery packs across the golf cart lifespan.
Related article:
Are Lithium Phosphate Batteries Better Than Ternary Lithium Batteries?
Understanding the Determinants of Golf Cart Battery Lifetime
