What is a Charge Algorithm? Answers to 8 Essential Questions That Will Fascinate Every Golf Cart Owner

If you own a golf cart, you may have heard of a charge algorithm, but might not be exactly sure what it is. In this blog post, we will explain what a charge algorithm does and how it impacts extending the life and performance of your golf cart's batteries. First, we should explain what an algorithm is.

1. What is an Algorithm?

At its core, an algorithm is a step-by-step set of instructions designed to perform a specific task or solve a particular problem. It takes an input, processes it through a sequence of clearly defined logic, and produces an output. The sequence stops after a finite amount time, ensuring it does not run indefinitely.

Algorithms are ubiquitous in computer science, serving as the backbone for tasks ranging from real-world applications like Google's search engine, Facebook's news feed, and even artificial intelligence.

2. What is a Charge Algorithm?

A charge algorithm is a specialized set of instructions that your battery charger follows. These instructions dictate how the charger should deliver power to the battery, ensuring it is charged optimally without causing damage. It considers multiple factors, including the battery chemistry, manufacturer, nominal voltage, and capacity. For instance, your charger will use a different algorithm for lead-acid batteries than it will for lithium.

3. Why is the Charge Algorithm So Important?

The charge algorithm ensures your batteries receive the right amount of power at the right time. Charging golf cart batteries with the correct algorithm can significantly extend the lifespan of your batteries. A properly charged battery ensures you achieve the maximum possible distance on a single charge.

Incorrect charging can lead to overheating, which can damage your batteries or even pose a fire hazard. In the case of lead-acid and AGM batteries, overcharging can result in the emission of harmful gases, posing additional health and safety risks. From a user experience standpoint, knowing that your golf cart's battery is fully charged safely provides peace of mind, enhancing your overall experience.

4. What are the Cycles in the Charge Algorithm?

Most charge profiles dictate the logic for a multi-stage charging process, including bulk, absorption, and finishing phases. Here are the steps in a four-stage charging cycle:

1.  Bulk Charge: The initial phase where most charging occurs.
2. Absorption Charge: The battery is charged at a slower rate to top it off without causing damage.
3. Float Charge: Maintains the battery at full charge, compensating for self-discharge.
4. Equalization Charge: Intentionally overcharges the batteries(usually by 10%), at a very low current (typically less than 0.5 amps), to bring the voltage in all the battery cells to similar levels. Additionally, equalization charges prevent sulfation and acid stratification.

Three-stage charge profiles are also very common, especially for lead-acid batteries, which do not have an equalization charge.

5. What is DV/DT?

DV/DT is a sophisticated charge termination method that refers to the rate of change in voltage with respect to time. In a DV/DT charge, the charger may initially apply a constant current (CC) to the battery until it reaches a certain voltage level. Once that voltage level is reached, the charger switches to a constant voltage (CV) mode.

During this CV phase, the charger monitors the rate of voltage change over time. When the rate of voltage change falls below a certain threshold, this indicates that the battery is nearly fully charged and the charger may either terminate the charge or switch to a trickle charge mode to maintain the battery at a full state.

This precise transition ensures optimal charging. This occurs in the Absorption stage, which is sometimes referred to as the "finishing" or "cool-down" cycle.

6. Can Charge Algorithms be Changed?

Absolutely! If you switch battery types, adjusting the charge algorithm is crucial. Using the wrong algorithm can reduce battery life or even pose safety risks.

7. Where Do I Find the Right Charge Algorithm For My Cart?

Charger manufacturers provide recommended charge algorithms for specific battery types. The manufacturer's website is the best place to find the correct algorithm for your charger. For instance, if you have a Lester Summit II charger, you can download the companion app to select your charge profile from your iPhone or Android device.

If you have a Delta-Q, charge profiles are available here.  If you are unsure or have a third-party charger, consult the battery manufacturer or a trusted golf cart dealer, like ACE of Carts, for guidance.

Final Thoughts

The charge algorithm is more than just a technical term; it is the heart of your golf cart's battery charging process. Ensuring you have the right algorithm for your battery type can make all the difference in performance and longevity. Always stay informed and consult experts when in doubt.