NiCD Battery Repair and Reconditioning
Nickel-Cadmium batteries have been around for over a century since their initial entry into the marketplace was all the way back in 1899. However, American production did not begin until far later in 1946, but since then they rapidly became some of the most ubiquitous batteries on the market with practically everything using them as a source of rechargeability so that the products could stay ready for use at almost all times.
The first step to NiCD batteries repair is to understand what they actually are. Basically, these type of batteries consists of a combination of Nickel Hydroxide and Cadmium that is held in a potassium hydroxide solution. Once production began in America, which was delayed because of the relative obscurity of the initial inventor Jungner’s work in that country, they were improved to a sintered version.
Sintering is a method of heating the plates to a temperature that is not enough to melt them so that a more porous surface is achieved, and this surface has a lessened internal resistance. Today’s modern versions now use an even more improved “Swiss roll” design.
How To Restore NiCad Batteries From The Memory Effect
One of the primary symptoms that creates the need for NiCD batteries repair is the fact that they are prone to be susceptible to what is known in the industry as the “Memory Effect.” With regular use, these cells will tend to discharge at a faster rate than when they are new.
Overcharging is one of the greatest contributors to this type of phenomenon, and when there is a need to revive a NiCad battery it may start to show as fully charged on a display when it actually is charged to a much lesser degree. This will, of course, provide a shorter lifespan in devices before it needs to be charged again, repeating the troublesome cycle.
A basic method of NiCad battery reconditioning, if this is occurring, is to allow the battery to reach a state of full discharge multiple times in a row before recharging again. This will usually help to restore things to a more expected state of operation. In fact, this type of discharge exercise should also be performed at a regular interval just to keep everything in an ideal state and as a preventative measure.
Recondition a NiCad Battery
The aforementioned memory effect can occur from too much overcharging, and then this can be combined in conjunction with other ill conditions such as excessive exposure to high temperatures and self-discharge in order to leave much to be desired in the operation of these batteries.
The cells begin to develop sulfur crystals that will work their way towards the terminals so that the recharge process is hindered. However, there is hope, and to recondition a NiCad battery that is in this state it is sometimes simply necessary to pass a high voltage current through these seemingly dead batteries.
Advanced NiCD Battery Repair
So what is the secret to getting these batteries that have built up a stubborn and resistant series of sulfur crystals? Well, there are a number of “homemade” methods that might actually be dangerous if a person who is not well experienced in electronics and such attempts them.
These primarily attempt to do NiCD battery repair with a car battery, and there is a danger of the toxic cadmium being exposed to the environment and workplace during an explosion or another mishap. This is because of the fact that a cell’s rate of temperature rise happens in relation to the inherent internal resistance and the square of the rate of charge.
It is not advised for the uninitiated to try this particular method. In any case, eye goggles and other safety equipment certainly provides a better degree of protection that should be sought.
Instead, a different simple method shows how to restore Nicad batteries with a capacitor that can be charged to a level that is around 2 to 4 times greater than the voltage of the cell that is being worked on. To recondition a Nicad battery in this way, it is then connected to the terminals with the polarities matching up.
This will allow the pulse to pass through the battery and help to eliminate the sulfur crystals that are limiting the function of the battery. Once this NiCD battery repair is complete, they are ready to be connected and charged again before being placed back into the device for an extended lifetime of great operation.
When looking at how to restore NiCad batteries safely, the presence of any special features should be noted in order to reduce the risk of venting and exposure. There is usually a pressure valve in the sealed variety of these cells, and that will attempt to contain any excess mix of hydrogen and oxygen gases.
Over time, these gases will recombine with water so that they are not an issue. But there is a limit to the amount that can be contained, and if that pressure is exceeded, then there is the danger of the battery having a reduced capacity if it has been overcharged to this level.
The cheaper variety of chargers are more likely to cause such a type of damage since there is a need for complicated detection circuitry in order to be able to detect whether a battery has reached this type of level.
NiCD Battery Repair and Reconditioning Wrap Up
NiCad batteries still hold a hot spot in the modern electronics market due to their prime ability to be used in such a diverse number of consumer devices while providing the rechargeability that so many desire.
There are quite a number of different types despite the seemingly cohesive quality that seems to group so many together in the same category. With a little forethought and the application of some electronic safeguards and protection strategies, these batteries can last a long time before needing replacement sometime in the future.