Everything you need to know about a UPS Backup Battery

In this article we aim to answer three FAQs about UPS batteries:

  • 1. How is a UPS backup battery made?
  • 2. What are the things you should look out for when purchasing a backup battery?
  • 3. Is my UPS battery really a green solution for Africa?

1. How is a UPS backup battery made?

The theory behind any battery is that if you put two different types of metals into a transferring medium there will be a power flow available which is called DC power.

The DC power is created due to a chemical reaction that takes place. This is what happens in all batteries; no matter what type, technology or claim to fame; the basic workings of all batteries are the same and follow the same process.

Can a lemon work as a battery?

In the case of a lemon battery, the citric acid (lemon juice – which is acidic) is the battery water also called the electrolyte. The electrolyte in a battery is never pure acid but rather a mixture of acid and water. The acid inside will never go away but only become stronger when the lemon loses water as it dries out.

When you insert two dissimilar metal probes into a battery the lemon’s acid causes a chemical charge which results in a transfer of electrons (part of an atom). This occurs between the two metal probes; one metal will attract the electrons and the other metal will give off the electrons. When this flow of electrons occurs it creates a power circuit or battery.

The most common UPS backup battery is a lead-acid backup battery. A lead-acid technology battery consists of a negative plate which is composed of one type of lead metal and a positive plate composed of another type of lead metal.

When you charge the lead-acid backup battery there is a transfer of electrons from one plate to the other plate via the transferring medium, which is as discussed earlier, is called the electrolyte. The electrolyte in a lead-acid battery is acidic by nature and is a weak form of sulphuric acid.

How much acid is inside a battery?

Any battery electrolyte can never be 100% pure acid or it would corrode any metal you put inside it. This is a big sacrifice made in any battery. The stronger the acid content in the electrolyte the better the battery will work, but, the stronger the electrolyte the more the battery’s dissimilar metals (also called plates) will corrode away. Eventually, the battery will not work as it will have no metals present.

With lead-acid batteries, there is always a sacrifice between the battery performance and the battery service life. This is why two batteries of the same rating, also known as the ampere-hour or AH, with the same size and weight, can vary greatly in performance and service life.

2. What are the things you should look out for when purchasing a backup battery?

Acid Content

Take the 7AH battery used commonly for backup power for alarm systems, electric gates, UPS units, etc. One product line will give you a 10-minute backup and another product will give you a 20-minute backup. This is mostly because the 20-minute product will have much more acid inside than the 10-minute product, so it will perform better. This higher acid percentage is also referred to as the Specific Gravity or SG.

Although the 20-minute higher-performing 7AH looks to be the best choice, the higher SG will mean that the battery plates will corrode more quickly and thus the battery will not last as long in its life; instead of the battery giving you, say, 5 years you may only get 2 or 3 years before it needs replacement.

On the other side of the scale, the battery with the lower SG, which may not perform as well for backup power, will last much longer.

Thick or thin plates

When a battery manufacturer produces a high rate battery i.e. high performance, they put thinner plates inside the same physical size plastic battery box. Because the positive and negative battery plates are now thinner, more of them can be fitted inside. More plates inside mean a bigger surface area of dissimilar metals to react with the electrolyte and thus the same size battery performs better.

With a stronger acid Percentage, or SG, and more plates equaling more surface area, the battery performance and backup are massively improved. This performance is achieved at the sacrifice of actual battery service life because the thinner plates corrode more quickly.

A lower performing battery will have a lower acid percentage or SG and fewer, thicker plates that don’t corrode away as easily as the thinner ones in a higher-performing battery product; this means it will last much longer in service.

Lead content

Another factor to bear in mind is that some battery manufacturers cheat. They put less lead inside with the same number of plates. Lead is the key component in a battery and responsible for the majority of the battery’s manufacturing costs. By reducing lead content there is a big saving on manufacture costs, resulting in a cheap battery product.

It is very important to look at the actual weight of a battery and compare it to similar battery products before buying the cheapest battery. If the cheapest battery is the heaviest, then usually it has more lead in it and will be a better product overall. We recommended that you buy well known UPS battery brands such as Enersys, ELITE, CSB, Vision, Chloride and Excide from FNB, etc.

3. Is my UPS battery really a green solution for Africa?

In Africa, there are very few battery recycling facilities. All the current recycling facilities that do exist in Africa are designed for 100% lead-acid battery technology product recycling.

Due mainly to the rolling blackout threat found in South Africa as a result of the ailing ESKOM infrastructure there is an ever-growing list of battery design technologies for use in Standby power backup systems, like a UPS or home inverter system.

The most common technologies include:

  • 1. VRLA sealed 3 to 5 or 10-year design life backup battery
  • 2. Lithium-Ion sealed maintenance-free backup battery
  • 3. Lithium Iron Phosphate also called Lithium Ferro or LiPHO4 sealed maintenance-free backup battery
  • 4. Lead crystal backup battery
  • 5. Nickel Cadmium battery which is highly toxic

All these standby battery technologies claim to be recyclable, but few say what percentage. Many battery manufacturers worldwide claim 100% recyclability but never state where the battery should be recycled.

As a citizen of the African continent, any UPS or standby power user should use only LEAD ACID TECHNOLOGY BATTERIES to prevent the further pollution and dumping of battery products in Africa, which are supposed to be shipped back overseas (at huge cost) for “recycling”.

This means high costs to the user, at the end of a battery’s life and use. There are no green alternatives for batteries in Africa other than the Lead Acid battery.