Why do rechargeable batteries deteriorate over time?
In: Engineering
[removed]
It’s like everything in life, nothing lasts forever. In simple terms, batteries are said to “age”, just like everything ages.
The compounds that make up the battery, the chemicals, deteriorate, become different compounds, and are no longer able to charge and discharge cleanly. So, over time, the compounds no longer work, and the battery stops working like in the beginning.
When using a battery, bits of one end dissolve and travel to the other end (or in most household batteries, from the inside to the outside). Recharging forces them back using an electric current, but they’ll never go back as cleanly as they first started.
Over time the electrodes continue to deteriorate, and the battery becomes less effective.
If something goes wrong (e.g. you try to recharge a non-rechargeable battery, or the control for a lithium battery breaks) it’s possible for the material being deposited to form a thin connection to the other side. This shorts out the battery, creating a lot of heat, and probably causing it to explode.
Batteries have what is called “internal resistance”. A battery is not a perfect open circuit, there is a bit of leakage from one node to the other, so eventually the battery self-discharges.
Internal resistance is a trade off: high resistance means the battery won’t self-discharge as fast but it also means the battery cannot supply high amounts of instanteous current, so that would be bad in something like a motor circuit.
heat, mostly.
the amount of energy it would take to fully reverse the reaction the battery uses to generate electricity would melt or burn it.
what’s interesting is that the reaction can be fully reversed, and that’s why car batteries aren’t such an environmental hazard despite being made of *lead.* they just need to be taken apart and the process done in an industrial vat.
Here’s a metaphor: a spring. The springy-ness of a spring deteriorates with use. Same thing with rechargeable. These lose their elasticity with use. The chemistry that changes to accept, hold and discharge electricity wears out.
Here let me Google that for you..
Result:
Why do rechargeable batteries weaken over time?
Charging a battery forces ions from the cathode to the anode; using the batteryreverses the flow. Over time, this process wears out the cathode, which results inreduced capacity. A high-end lithium-polymerbattery can lose about 20 percent of its capacity after 1000 charge cycles.
Google is easy to use.
Latest Answers