when it is desired to connect cells in series? in parallel?
When it is desired to connect cells in series, it typically means that you want to increase the total voltage. Connecting cells in series involves connecting the positive terminal of one cell to the negative terminal of the next cell, and so on, forming a chain. By doing this, the voltages of each cell add up. For example, if you connect two 1.5V cells in series, the total voltage would be 3V (1.5V + 1.5V). This configuration is commonly used in devices that require a higher voltage, such as flashlights or electronic circuits.
On the other hand, when it is desired to connect cells in parallel, the goal is typically to increase the total current capacity. Connecting cells in parallel means connecting all the positive terminals together and all the negative terminals together. This configuration allows the cells to share the load, resulting in a higher combined current capacity. For example, if you connect two 1.5V cells with a capacity of 1000mAh in parallel, the total voltage remains 1.5V, but the capacity doubles, resulting in a total capacity of 2000mAh. This setup is often used in high-drain applications, such as electric vehicles or power tools, where a higher current is required.
It's important to note that when connecting cells in series or parallel, you should use cells of the same voltage and capacity to ensure proper operation and avoid potential damage to the cells.