How many separate lithium-ion cells are contained in a 48-volt battery?
To determine the number of lithium-ion cells in a 48-volt battery, we first identify the nominal voltage of a single lithium-ion cell, which is typically \(3.6\text{ V}\) or \(3.7\text{ V}\). To form a 48-volt battery, cells are arranged in a series configuration (denoted by 's'). For a 14s configuration, the nominal voltage is \(14 \times 3.6\text{ V} = 50.4\text{ V}\) or \(14 \times 3.7\text{ V} = 51.8\text{ V}\), which is commonly marketed as a 48-volt battery pack. In such a configuration, the total number of cells is determined by the number of series-connected groups multiplied by the number of parallel-connected cells (denoted by 'p'). Examining the provided options \(24\), \(32\), \(45\), and \(28\), we check for values divisible by the standard series count. The value \(28\) is exactly \(14 \times 2\), representing a \(14\text{s}2\text{p}\) configuration. This is a very common and standardized construction for a 48-volt lithium-ion battery pack.
We have identified that a 48-volt lithium-ion battery system typically follows a 14s (series) configuration. By testing the provided options against this standard, we find that 28 is the only value that corresponds to a simple, standard parallel multiplier for a 14s configuration (14 series groups in a 2 parallel arrangement, i.e., 14s2p). Therefore, 28 is the logical choice for the number of cells in the battery.
Lithium-ion battery packs are modular systems found in electric bicycles, power tools, and even energy storage units for homes. By understanding that a battery pack is composed of cells connected in series to increase voltage and in parallel to increase capacity, a user can correctly estimate the capacity and voltage of their system based on the total number of cells. For instance, knowing a battery contains 28 cells in a 14s2p configuration helps in selecting the correct charger and ensuring compatibility with the motor or device being powered. This foundational knowledge of battery architecture is essential for safety, maintenance, and efficient use of modern portable power technologies.