Deep Cycle Batteries

What is a Deep Cycle Battery?

Actually, this is not a technology battery at all. It is a collective name for several types of batteries with the same characteristic. Freely translated, it means Deep discharge. So this type of battery can be deeply discharged and are therefore suitable for service applications, or for electrically powered vehicles.

So What Exactly is a Cycle?

A cycle means discharging to a certain discharge percentage and charging to 100%. This process is also called a cycle. To what percentage the battery is discharged is expressed in D.O.D.. This stands for Depth of Discharge.

In other words, how deeply do I discharge my product. This is always expressed in percentages. So if you half-discharge the battery, you call this a discharge to 50% D.o.d.. Then charge the product again to 100%. Then that's 1 cycle at a 50% discharge.

Why Are Cycles Important?

So the Deep cycle battery can be deeply discharged. As we have read above, this is expressed in D.o.d.. But with these cycles you can also express the lifespan of the product. This process as described earlier can keep the battery a number of times full.

When referring to a battery, the term "deep discharge" indicates that the battery has had practically all of its charge drained from it.

How many times it can do this is then the service life. For example, the battery is deep cycle for 50% discharge. It can do this 400 times. So it will last 400 cycles if it is discharged to this percentage! So now you can compare the differences in battery life of different brands and types.

Comparing Deep Cycle Lead-Acid and Lithium-Ion Batteries for Home Power Storage

The Tesla Powerwall uses lithium-Ion technology, in contrast to other solar battery banks that are common in the renewable energy field, which are normally produced with deep cycle lead acid technology. Most likely, lithium-ion will also be used in the products we already have from major manufacturers like Samsung, Panasonic, LG, and Schneider Electric.

Does lithium-Ion have a certain edge over the Lead-cycle, given that the major corporations are headed in that direction? Yes and no, I suppose. Both have benefits and drawbacks of their own. You will decide which option is the better one after reading this article's attempt to explain the differences between the two.

First, I'd like to go over some of the key ways in which they differ.

The Major Differences

The two battery technologies are more unlike than comparable, and the following are the most salient distinctions:

When compared to lead-acid batteries, lithium-ion batteries are typically 30% less in weight.
Lithium-ion batteries can be charged to 100% and discharged with 80% efficiency. However, the charge-discharge efficiency of deep-cycle lead acid batteries is normally lower than 80% and can be as high as 95%.
Lifespan between 2,000 and 4,000 cycles is typical for Li-ion batteries, with the best lasting up to 5,000 cycles. The typical lifespan of a lead acid battery is between 400 and 1,500 cycles.
Battery Voltage: Compared to deep-cycle lead acid batteries, lithium-ion batteries maintain a consistent voltage throughout their discharge cycle (sloping voltage.)
Lead-acid batteries are among the least expensive options on the market, both initially and in terms of cost per kilowatt-hour. However, Li-ion is one of the more pricy options.
Electrolytes and lead in lead-acid batteries are harmful to the environment. Compared to previous technologies, Li-ion cells are substantially less hazardous to the natural world.

After going over the broad strokes of the differences between the two, we will now delve deeper into one of the most essential characteristics of batteries, which is the amount of time it takes to charge.

The Difference in Charging Times

One of the areas in which lithium-ion batteries excel most prominently is in their charging times. When compared to lead-acid batteries, lithium-ion batteries have a charging time that is ten times faster.

This is primarily due to the fact that lead acid batteries can only withstand a charge rate of approximately 0.2C (0.2 times their capacity), which indicates that we can only charge a battery with a current of 100 A if it has a capacity of 500 A. If you go beyond that, the battery will overheat, which will make the charging process even more drawn out.

On the other hand, Li-ion can tolerate being charged to a level that is five times greater than its capacity, although 0.5C is the level that is recommended. This means that the same battery that can handle 500 Amps of current can also handle 250 Amps of charging current.

However, lithium-ion batteries cannot withstand overcharging, which occurs when the battery is continued to be charged after its capacity has been reached. Lead-acid batteries, on the other hand, are able to do so without issue, and the process results in the formation of hydrogen gas from the battery's excess capacity.

Deep cycle batteries are the standard when it comes to lead acid batteries. However, not all lead acid batteries can withstand deep cycling. The battery itself makes this information clear. They are often referred to by the more specific name "marine batteries" due to their widespread application in watercraft.

Because of this, a Li-ion battery needs to have a protection circuitry built into it in order to control overcharging, overvoltage, and its discharge. This protection circuitry needs to be custom-made, which adds even more expense to an item that is already quite pricey.

In light of the foregoing, it should come as no surprise that Li-ion batteries come out on top in terms of the most effective use of charging time. Now that we've covered that, let's talk about the cycle lifetime.

Evaluation of Life Cycle

Current lithium-ion batteries have an average lifetime expectation of 2,000-4,000 cycles, compared to 400-1,500 cycles for lead-acid batteries. The life cycle of batteries will depend on how you use it, temperatures, and many other factors; however, the average lifespan of lithium-ion batteries is 2,000-4,000 cycles.

A period of time during which a battery is charged and then discharged is referred to as a cycle. One cycle is defined as the single instance in which a fully charged battery is discharged to its utmost capacity.

Once again, Li-ion comes out on top, and unlike lead-acid batteries, lithium-ion batteries won't need to be replaced nearly as often.

Safety Precautions

Can you figure this one out? Yes, lithium-ion is another victor in this competition; however, there is a catch with this one. In a general sense, lithium and lead acid are both toxic substances, which means they are hazardous to both the human body and the environment.

Because of technological advancements, ionization of lithium is now possible, which resulted in the production of the more secure lithium-ion compound at the expense of energy density. There have been instances of Li-ion batteries spontaneously catching fire and exploding, as we can see happen to electric vehicles in many viral videos circulating the web, as well as similar incidents with cellphones and laptops.

The dangers associated with Li-ion batteries were dissected in great detail during the Battery University (https://batteryuniversity.com/article/lithium-ion-safety-concerns) presentation. Their research led them to the following conclusion: heat-related accidents are extremely uncommon, and the majority of lithium-ion batteries are designed with three layers of safety measures: the limitation of the lithium-ion in a safety level; various safety mechanisms within the cell; and an electronic protection circuit.

Deep cycle lead-acid batteries, on the other hand, produce hydrogen when they are overcharged and continue to produce electrolytes even when they are not charging. Not to mention the fact that lead acid is a very dangerous substance in and of itself. However, they are also fitted with safety mechanisms to cut down on the dangers that could potentially be posed.

A Li-ion battery in its most basic form is probably the most dangerous type of rechargeable battery. However, a number of different technologies and safety mechanisms are utilized, which contribute to its increased safety, making it one of the safest battery options available on the market. What's the catch? These preventative measures have an impact on the topic we're going to talk about next, which is cost.

Considering Cost

After considering all of the contrasting options, determining the solution to this problem is almost embarrassingly simple. While it's true that lithium-ion batteries are more expensive, their advantages make them worthwhile.

Although the price per cell has decreased, the average cost of a lithium-ion battery is between $300 and $400. On the other hand, lead-acid batteries have a cell cost of less than $100 on average.

Price reductions are expected to continue over the next five years, according to both economists and tech sector professionals. When you consider that Tesla is in the process of constructing its gigafactory with the goal of reducing the price of their Powerwall cell to less than $100, this becomes even more apparent.

When Do You Use A Deep Cycle Battery?

For uses that demand more than just a kick start, deep-cycle batteries are the best option. The following is a list of some of the most prevalent applications for deep cycle batteries:

Marine applications
Vehicles for leisure or recreation
Handling of materials, including the use of forklifts
Carts used for golfing
Alternative energy sources that are not connected to the grid

Hybrid batteries are an alternative solution that can be used for some applications, particularly marine usage. A hybrid marine battery has the ability to provide both a burst of starting power and sustained power for maritime applications; however, its lifespan is often lower than that of a battery that is dedicated to a specific function.

The Different Types of Deep Cycle Batteries

There is a variety of deep cycle batteries, each with its own unique set of features. Both flooded deep cycle batteries, and sealed deep cycle batteries, sometimes known as "maintenance-free" deep cycle batteries, are considered to be the most prevalent forms of deep cycle batteries.

Flooded Deep Cycle Batteries

Monitoring is required on a regular basis for flooded deep cycle batteries. When the electrolyte levels in a battery of this type become low, the user is responsible for properly topping off the battery in order to keep the battery's performance stable.

Maintenance Free Batteries

"Maintenance-free" batteries, also known as "Sealed" or "Valve Regulated Lead Acid" batteries, are hermetically sealed and do not need to be topped off with water. However, it is still advised that they be inspected on a regular basis.

It is crucial, whether you are a consumer or a battery dealer, to have an understanding of the many tasks that different types of batteries serve. Although the contrast between a standard battery and a deep cycle battery may not matter much to the typical person, the more you know, the better you will be able to make effective power storage options to meet all of your requirements.

Summary: Analyzing Relevant Domestic Electricity Use

After going through everything that differentiates the two possibilities, we are able to draw the following conclusion: lithium-ion is unquestionably the superior choice, despite the fact that it is more costly.

Therefore, when thinking about either one of these as a possibility for the energy storage in your home, the question that should be asked is not one of the benefits and drawbacks of each, but rather whether or not it will be worthwhile.

To provide an educated response to this question, let's take a step back and go over some of the key benefits of using lithium-ion batteries once more:

Weight: Weight is clearly a major benefit for Li-ion in applications like cell phones and notebooks, which demand mobility. Li-ion batteries are thinner and lighter than other battery technologies. On the other hand, for applications involving the storage of energy in the home, this is not a deciding consideration because, with a few exceptions, the battery will be installed on the wall.

Charging Time: Because you will be harnessing the boundless power of the sun or the wind as your primary source of power, you will have an infinite amount of time to charge your device, providing that the solar or wind power system you have installed was constructed correctly. Lead-acid batteries are still a viable option, provided that you do not reside in an environment that is exceptionally severe.

Lead-acid batteries can be totally safe for human use if the proper handling procedures are followed, and they also have a low impact on the environment. However, depending on how you feel about the effects that human activity has on the environment, the more environmentally friendly energy that lithium-ion provides might be worth the additional cost.

It is possible that purchasing one lithium-ion battery will be more expensive than purchasing two lead-acid batteries over the course of a lifetime. Therefore, replacing a lead-acid battery is still a preferable alternative to making the financial investment in a lithium-ion battery.

However, there is an additional benefit that you should take into consideration, and that is the luxury of simplicity.

Investing in a lithium-ion home battery will provide a sense of luxury and security with its warranty and after-service from certified technicians. These large companies, such as Tesla, Panasonic, LG, Schneider Electric, and Samsung, are just a few of the companies that will likely produce lithium-ion home batteries in the near future.

Is it really worth the price? We will defer to your judgment on this matter.