Determining the cost of a battery pack with fuel gauge technology will vary depending on the accuracy of the battery fuel gauge required. The overall size of the battery pack will also have an effect on the final cost. For example, if a high-accuracy gauge is required on a small multi-cell battery, it could potentially double the cost. The good news is that the cost of battery cells become relatively small when factoring in the added value received from implementing a fuel gauge.
If your application does not require a fuel gauge with the highest accuracy, depending on by the size of the battery, it may only add an additional 10% to the price because the overall cost goes into the actual cells and the energy density of the battery. Each application will differentiate; if cost is a deciding factor, we can offer trade-offs to find the best solution based on your specifications.
What is a Battery Fuel Gauge?
A battery fuel gauge informs the user how much power (battery life) is left in relation to total battery charging capacities. We actually use products with fuel gauges every day in electronics that run on battery power. Portable electronic devices, like your cell phone, are the most widely used example. There are a couple different ways in which fuel gauging can be achieved within your custom battery pack design. One way is through Voltage Lookup, which is the state of charge that can be determined by measuring battery voltage and comparing it with an internal lookup table. Another method is through Coulomb Counting, this is the total amount of energy entering and leaving the battery measured. Last is by using a combination of both voltage lookup and coulomb counting. This method offers the advantage of having each method balance any inaccuracies between the two types of readings.
Custom Battery Pack with a Built in Fuel Gauge
Additionally, the Texas Instruments (TI)'s impedance tracking fuel gauge technology offers further solution to issues with inaccurate readings due to aging and battery temperature. Using impedance tracking, the battery pack fuel gauge may be programmed to be accurate within 1% for the life of the battery. Accurate fuel gauges allow batteries to be discharged to almost empty confidence; hence, batteries do not need to be oversized making them smaller, lighter, and more dependable.
Visit our website for more information on our battery pack capabilities or see our technical article on how Added Value Electronics Can Turn Normal Batteries into Smart Battery Packs.