Rechargeable batteries-9 significant things to know

There are 95% of population which uses rechargeable batteries in their day to day life. If we look at our surroundings we can observe that our lives are basically running on rechargeable batteries from mobile phone batteries to power tool batteries and car batteries.

We are using rechargeable batteries like never before. Rechargeable battery is a type of battery that can be charged after being discharged by applying DC charge to its both terminals. This article will share 9 important things you should know about rechargeable batteries.

What are the types of rechargeable batteries-are rechargeable batteries worth it

Batteries are generally classified into many categories based on different factors like chemical composition, sizes, form factors, etc. Among them, the two major classifications are primary cells and secondary cells.Let’s look a little deeper into the primary cell and secondary cell.

Non rechargeable batteries are termed as primary cells. The chemical reaction here is non reversible in nature. They are basically used in applications where charging is impossible or impractical. Some of the devices in which we use primary cells are pacemakers, children toys, watches etc.

Rechargeable batteries are termed as secondary cells. These cells are electrically rechargeable once discharged at their predefined rate.In this article we are going to focus more on classification based on materials of the rechargeable batteries. The most commonly used rechargeable batteries are as follows.

● Nickel cadmium batteries ( Ni-Cd ):

It is a kind of old battery available in the market which was developed using nickel oxide hydroxide and metallic cadmium to act as electrodes. These types of rechargeable batteries have a relatively long cycle life of 1000-2000 times which is lower than lithium ion batteries of 4000 times.

They also has serious memory effect while lithium ion batteries never need to suffer this. Nickel cadmium batteries are available in different sizes from AAA to D. The chromium in the Nicd battery is a harmful substance, which can affect the environment and is not environmentally friendly.

● Nickel-metal hydride batteries ( Ni-MH ):

It is a kind of rechargeable battery which is more expensive than Nicad battery.It has many advantages over Ni-Cd batteries such as it can be partially charged and discharge as many times as required without harming their life span because it has small memory effect.

However, it is better to recharge and charge once after each use.The chemical reaction at the positive electrode is similar to that of Ni-Cd and the negative electrode in Ni-MH uses a hydrogen absorbing chemical instead of cadmium.

Its applications include high drain devices because it has high capacity and energy density than Ni-Cd. Although Ni-MH batteries has a high energy density of 30-80wh/kg, lithium ion batteries’ energy density is much higher, which reaches 100-140 wh/kg. And the cycle life of Nimh batteries is low, only half that of Nicd batteries.

● Lithium-ion batteries ( Li-Ion ):

This battery solves all the problems with both the batteries we learned before i.e it has full voltage of 3.2v-3.7v and also suffers no memory problems. It also has a high energy density and a cycle life of up to 4,000 times. Lithium ion battery is one of the most popular rechargeable batteries at present.

Its popular applications include powertools, golf carts,RVs, UPS solar system and so on.In addition to the high energy density, long cycle life and little memory effect, they also have other advantages including light weight, no environmental pollution and low self discharge rate of 3.5% per month.

● Lead acid batteries:

These batteries are basically used in heavy duty applications. They are the oldest types of rechargeable batteries and still used by some devices today. It has very low energy to volume and energy to weight ratios but has a relatively large power to weight ratio, which is capable of supplying a huge surge current when needed.

Under the same size, the weight of lithium-ion battery is 30% of that of lead-acid battery. The electric energy conversion efficiency of lead-acid battery is about 80%, while that of lithium-ion battery is more than 97%.

Are rechargeable batteries worth it? Yes, they are definitely worth as they have a list of pros when compared to non rechargeable batteries.

● Longer lasting batteries
● Better performance
● Less expensive
● Less product waste
● Better for environment

Which rechargeable battery is best

Here presenting the list of the specifications and value according to different rechargeable batteries.

Table 1. specifications and value of different rechargeable batteries

How do I choose a rechargeable battery

The major factors to consider before buying rechargeable batteries are as follows :

● Cycle life:

Three major types of rechargeable batteries are Li-On, Ni-Cad and NiMH. While Nicd can be charged for 1000-2000 times and NiMh be 500-1500, lithium ion battery has a much higher cycle life of up to 4000 times.

● Voltage:

Voltage of the batteries are defined by the electrodes and electrolyte used.

● Temperature:

This factor also depends on battery chemistry.Lithium ion battery can be used in the temperature between -20℃ to 60℃.

● Size/Shape:

Batteries can come in different shapes such as coin/button cells, cylindrical, prismatic, pouch type cells.

● Energy and power:

Get to know about battery energy in Wh by multiplying the battery voltage by its capacity in Ah.

How do you store rechargeable batteries when not in use

To store rechargeable batteries we need to keep in check a few things such as room temperature, container you are using to store them, etc. Try to store them in a non-metal container and place them at a cool dry place until you are ready to dispose of them.

The Environmental Protection Agency (EPA) suggests taping the both terminals of used batteries with electrical tape or placing each battery in separate plastic bags. Batteries that kept together could rub against each other and could lead to short circuit and fire.

Do rechargeable batteries last forever-which rechargeable battery has the longest life

Most rechargeable batteries have a charge cycle of around 1000 times which means it can work for several years. But lithium ion battery has the longest cycle life of up to 4000 times in the present market.

The life of rechargeable battery is generally calculated according to the number of cycles. It is a cycle from full charge to discharge. Therefore, the more frequently the battery is used, the more cycles it consumes, and the shorter the overall service time.

What are the disadvantages of rechargeable batteries

One of the most mentioned disadvantages is that rechargeable batteries are priced higher than disposable batteries, but that’s just the initial cost. Rechargeable batteries can last longer, which is more cost-effective in the long run.

Another disadvantage is that it can become weak and less predictable with age and it also needs a battery management system. The BMS of professional battery factory adopts intelligent high-end imported chip BMS system, which can monitor the battery status in real time and provide multi-level warning.

How to charge rechargeable batteries

The very 1st step which you need to follow is to bring a proper battery charger for the battery you need to charge. For example, if you want to charge a lithium ion battery, you should use a lithium ion battery charger to chage.Then plug the charger into an outlet which is meant to charge these kinds of batteries. Be careful about the configuration of the batteries.

How long do rechargeable batteries take to charge

Time taken by batteries to charge fully depends on the type and specification of battery you are using. Charging time also depends on the charge rate of batteries. For example, if lithium-ion batteries have a charge rate of 0.2C, so it takes five hours to charge.

How do you know when a rechargeable battery is fully charged

Many rechargeable batteries have green light that will light up when a battery is fully charged. So if you are seeing red light instead of green then keep your battery on charge. Regular battery manufacturers will equip lithium-ion batteries with BMS to protect the circuit from explosion or fire caused by overcharge.

The BMS of regular battery manufacturers adopts intelligent high-end imported chip BMS system, which can monitor the battery status in real time and provide multi-level warning.

Can I use any charger for rechargeable batteries

No, it would not be wise to use any charger to charge any rechargeable battery. Battery charger uses specific charging protocols for specific battery chemistry. Furthermore, it may cause explosion or fire if you use any charger for rechargeable batteries.

The application of the rechargeable batteries

What devices are rechargeable batteries good for

Devices which are good for rechargeable batteries like lithium ion battery are as follows :

● UPS ( uninterruptible power supply )
● Dependable electric and recreational vehicle power
● Reliable and lightweight marine equipments
● Solar power storage
● Surveillance or alarm systems in remote locations
● Powerwall
● Portable power station

Can you use rechargeable batteries in anything

No, we can’t use rechargeable batteries in anything. For example, It is better not to use rechargeable batteries for the air conditioner remote controller. The rechargeable battery will have voltage difference after charging and discharging for a period of time, which will easily damage the infrared transmitter of the air conditioner remote controller.

How to deal with the problem using rechargeable batteries

Try to be careful about battery health and maintain all the precautions that come with batteries to ensure long life of the battery.

What causes a rechargeable battery to fail

Improper storage could be one of the reasons for failure of rechargeable batteries. High cutoff voltage, electrical leakage, ageing, internal resistance could be few reasons for battery failure.

How do you know when rechargeable batteries are dead

Just check the cell voltage by using a multimeter. Lets understand with an example, if you are using NiMH battery then it will fully discharge at 1V, so if any of your cells are going down to this quickly then they are dead.There are many tricks which you can try to revive your dead rechargeable batteries. Here is one of them.

Firstly prepare a metal barbecue tong. Then take a fully charged battery and your dead battery and hold the two negative ends in a way that they are touching. Hold them together between tongs for 30 secs. Then you can charge your dead rechargeable battery as usual.