Discussion Overview
The discussion revolves around the observed voltage across a 9.7 volt battery pack while it is discharging. Participants explore the reasons for a significant voltage drop from 9.4V (not in use) to 5.8V (in use), questioning the behavior of batteries under load and the implications of internal resistance.
Discussion Character
- Exploratory
- Technical explanation
- Debate/contested
Main Points Raised
- One participant notes that batteries are not perfect emf sources and that internal resistance can cause voltage drops under load.
- Another participant challenges the extent of the voltage drop due to internal resistance, suggesting that a drop of 3.6V is unacceptable given typical internal resistance values.
- A formula is presented to describe how the voltage delivered to a load depends on both load resistance and internal resistance.
- There is a clarification that the original question pertains to the voltage across the battery itself, not across a resistive load.
- Concerns are raised about the battery's ability to handle high current withdrawal, suggesting that excessive current draw could lead to significant voltage loss.
- A participant mentions the possibility of the battery being near the end of its charge or failing, referencing open circuit voltage characteristics.
- Another participant introduces the concept that the voltage of an electrochemical cell is concentration dependent, implying that prolonged use can lead to a drop in voltage.
Areas of Agreement / Disagreement
Participants express differing views on the causes of the voltage drop, with some attributing it to internal resistance and others suggesting the battery's state of charge or health. There is no consensus on the exact reason for the observed voltage behavior.
Contextual Notes
Participants mention various factors that could influence battery performance, including internal resistance, load characteristics, and the state of charge, but do not resolve the implications of these factors on the observed voltage drop.