It’s not uncommon to find an old battery lost in the bottom of a box or drawer, but it’s often difficult to know how much charge is left. Since type objects do not have visual indicators to indicate whether they are complete or empty, this is a very traditional method of obtaining information, and Canaltech explains what it is.
What is a bounce test?
To realize the charge of the pile, drop only a few centimeters in relation to the smooth surface. It is not recommended to leave the mound too high, as this can cause physical damage, as well as disrupt the results of the experiment.
Proper placement of the test has the positive side of the battery in front — that is, a small bulging tip. The negative (and therefore smooth) side will be on the underside and will make direct contact with the surface.
In addition, it is important to avoid experimenting with wooden tables or benches or other more flexible materials. The hardness of the selected surface is directly proportional to the level of accuracy of the results.
If the product stays upright, it is still likely to store a large amount of charge. Thus, the battery can still be used in remote controls, peripherals and many other devices.
However, if the battery runs out, it may be time to buy a new one. Nevertheless, it is advisable to repeat the tests a few times to make sure the charge is complete – it is also recommended to compare the results with a battery whose charge is already known, whether it is full or empty.
But why does this happen?
The battery or batteries accumulate zinc oxide on the inside, which forms a substance with small spring-like properties and is therefore more likely to “bounce”. New elements have a good ability to absorb this effect, so the stack is able to stay straight.
However, an important distinction must be made. The side batteries are not empty: it is possible that the chemical incident is partial, but there is still a small percentage of charge left.
Therefore, the method of leaving the stack cannot be considered 100% reliable. To get more accurate results, special equipment must be used.
Measure the load with a multimeter or tester
People who find themselves in the situation described above can take advantage of the usefulness of a multimeter. This type of equipment is available in many stores for less than R $ 50, but more advanced models are also available for higher prices.
To configure a multimeter, simply turn the selector to the direct current portion, which can be represented by the letter V next to two lines: one continuous and the other dash.
Some models still need to choose the measurement scale – in these cases, as long as it is higher than the voltage indicated on the side of the battery, you need to choose the lowest possible voltage. For example, if the stack is 1.5V, the 2000 mV (2V) option would be most favorable.
Next, multimeter cables need to be placed on both sides of the stack. Red lead goes to the positive side, black lead goes to the negative side – no need to worry about electric shock.
If the steps are followed correctly, a numerical value will appear on the LCD display. If this number is the same as the number shown on the side of the stack, it means the stack is full.
However, lower values may indicate that it is time to replace the battery. This relationship is not linear, meaning that a number greater than zero can also indicate that there is not enough charge balance.
There is another special device to check the battery charge. It is a tester, a device made up of two main parts: a compartment for batteries of different sizes and a visual indicator with a pointer indicating green, yellow or red.
Its use is quite intuitive: just turn on the equipment, plug in the battery and identify where the pointer stops. If it stays red, it’s time to get a new stack.
Source: 12Tomatoes, GH, The Conversation