There are primarily three ways to connect battery cells: in series, in parallel, or a combination of both called series-parallel. Each method affects the overall voltage and current output of the battery system.
Battery Cell Connection Types
Here's a breakdown of the different connection types:
1. Series Connection
- How it Works: Cells are connected end-to-end, positive terminal to negative terminal.
- Voltage: The voltage of each cell is added together. For example, if you connect two 1.5V cells in series, you'll get a 3V output.
- Current: The current capacity (Amps or Amps/hour) remains the same as a single cell.
- Use Case: Used when you need a higher voltage than what a single cell can provide.
- Example: Flashlights, remote controls often use series connections to achieve the necessary operating voltage.
2. Parallel Connection
- How it Works: Cells are connected side-by-side, positive terminal to positive terminal, and negative terminal to negative terminal.
- Voltage: The overall voltage remains the same as a single cell.
- Current: The current capacity is the sum of the individual cells' current capacity. For instance, two 1000mAh cells in parallel provide a 2000mAh capacity.
- Use Case: Used when you need more current than what a single cell can deliver, extending the run time for devices.
- Example: Some power banks, large capacity battery packs in tools might connect cells in parallel for increased runtime.
3. Series-Parallel Connection
- How it Works: Cells are connected in groups of series and then these groups are connected in parallel. This approach helps meet both the voltage and current requirements.
- Voltage: The voltage is increased from series connection and remains the same for parallel groups.
- Current: The current capacity is increased based on the number of parallel groups.
- Use Case: Common in many high-power applications requiring both high voltage and high current.
- Example: Electric vehicles, power tools, and solar power storage systems that need a specific operating voltage and longer run time.
- Reference: As highlighted in the reference, batteries can be connected in a mixture of both series and parallel. This combination is referred to as a series-parallel battery. Sometimes the load may require more voltage and current than what an individual battery cell can offer.
Table Summary
| Connection Type | Voltage | Current Capacity | Use Case |
|---|---|---|---|
| Series | Added together | Stays same as a single cell | Higher voltage needed |
| Parallel | Stays same as a single cell | Added together | Higher current/runtime needed |
| Series-Parallel | Voltage increased, stays same across parallel groups | Current is increased based on parallel groups | Both high voltage and high current required |
