Key Questions to Ask When Ordering Lead Acid Battery

Source: Veer

View Details

Lead acid batteries have a long history of development and a wide range of applications. If you are reading this article, you obviously have some questions about lead acid batteries. For example, what is a lead acid battery? How does a lead acid battery work? Fortunately, we will provide a complete guide on lead acid battery.

What Is a Lead Acid Battery?

Source: pixabay

Lead acid batteries are rechargeable batteries that use lead and sulfuric acid to work. Immersion of lead in sulfuric acid allows for controlled chemical reactions, which is the reason why batteries generate electricity. The reaction is then reversed to charge the battery. It is worth mentioning that this technology has a history of over 100 years. Since its invention in , lead acid batteries have been improved, and now they work more efficiently. Therefore, this article briefly introduces the working principle and main types of lead acid batteries.

How Does It Work?

Source: Microsoft Bing

Because sulfuric acid is used as an electrolyte in batteries, when it dissolves, its molecules are dispersed in the form of SO4-(negative ions) and 2H+(positive ions), which move freely. The positive ions move towards the negative edge of the battery, and the negative ions move towards the positive edge of the battery. Each hydrogen ion and sulfate ion collects one and two electrons and negative ions from the cathode and anode, which react with water to produce hydrogen and sulfuric acid. The product generated by the above reaction reacts with lead oxide to form lead peroxide.

During this process, through wire connections, current flows through an external circuit from the negative electrode plate to the positive electrode plate, which makes the battery capable of supplying power.

There are 4 main types of lead acid batteries, which are described in turn below.

FLA(Flooded Lead Acid Battery)

Source: Microsoft Bing

Introduction

This type of lead acid battery is a traditional engine ignition type with a traction battery. The electrolyte moves freely in the battery section. During using, the water in the electrolyte will evaporate and need to be regularly topped up. This maintenance procedure is very important, and if not completed, it will lead to battery damage. Liquid rich lead acid batteries must be kept in an upright or vertical position. When the battery is overturned, the acid can leak through the vent and cause damage because sulfuric acid is highly corrosive.

Pros

Flooded lead acid batteries have existed for more than a decade. Despite various limitations, they are also the cheapest type due to their low manufacturing costs and easy access to raw materials, making them the choice of many users. Also, this battery has a longer lifespan than other batteries.

Cons

There is a cover on the top of a rich liquid battery that can ventilate and prevent liquid splashing. Due to the evaporation and decomposition loss of water during use, it is necessary to regularly open the cover to add distilled water and adjust the density of the electrolyte. Traditionally, it is called an “open type” battery. Because of this, its disadvantage is that users need frequent maintenance, which increases the inconvenience of use.

Application

Flooded batteries are common in many applications and are the choice of many renewable energy and RV owners. Specific applications include automotive starter batteries, motorcycle batteries, ATV batteries, golf cart batteries, and solar and emergency backup systems.

SLA(Sealed Lead Acid Battery)

Source: Veer

Introduction

Sealed lead acid batteries are very similar to flooded lead acid batteries, but users cannot access the internal compartment, which means they do not have to add distilled water to maintain the battery’s operation. The electrolyte is sealed inside, enough to allow the battery to live for a sufficient number of cycles. Sealed lead acid batteries, also known as maintenance free batteries, are divided into two types: AGM sealed lead acid batteries and GEL sealed lead acid batteries.

AGM

• Introduction

Source: pixabay

AGM type batteries use a pure sulfuric acid aqueous solution as the electrolyte, most of which is present in a glass fiber membrane, and a portion of the electrolyte is absorbed inside the electrode plate. The AGM type sealed lead acid battery has a small amount of electrolyte, a thicker electrode plate, and a lower utilization rate of active substances than the open type battery.

• Pros

Compared with the same specification battery with flooded batteries type, it has the following advantages: the cycle charging capacity is 3 times higher than that of lead calcium batteries, and it has a longer service life. AGM lead acid batteries also have higher capacitance stability and more reliable low-temperature performance throughout the entire service life cycle.

• Cons

Due to the expensive raw materials of AGM, it is more expensive than flooded lead acid batteries, but at this price, you can enjoy the convenience of not having to maintain the battery or handle gas during the charging phase.

• Application

AGM batteries are ideal for mobile applications such as motor home batteries, marine batteries, motorcycle batteries, ATV batteries, and UPS and telecommunications batteries for generators.

Gel

Source: Microsoft Bing

• Introduction

The working principle of gel lead acid battery is similar to that of AGM battery, because the electrolyte is suspended, but the difference is that technically, AGM battery is still regarded as a wet battery. The electrolyte in the gel battery contains silicon dioxide additives, which can solidify or harden it, making its charging voltage lower than that of other types of lead-acid batteries.

• Pros

For this type of battery, it is widely used because they improve efficiency and design safety features. They generate most of the gas (hydrogen and oxygen) during internal recombination charging, so no additional maintenance is required. The batteries also last longer at warmer temperatures, so if you are exposed to higher enclosed temperatures for a long time, you can choose to use them.

• Cons

Gel lead acid batteries are not only the most expensive VRLA battery, but also the most sensitive VRLA battery. The production cost of gel batteries is relatively expensive, so they are not ideal for use in environments other than a few specific solar applications (mainly in very hot climates).

• Application

The design of gel electrolyte batteries is usually quite old, and there are few engineering options to improve them. Although not as common as AGM batteries, they often occur in situations of deep discharge, such as wheelchair and medical mobile batteries, trawler batteries, and RV deep cycle batteries.

Deep Cycle Lead Acid Battery

Source: Microsoft Bing

Introduction

A deep cycle lead acid battery is a battery designed to use most of its capacity for periodic deep discharge. For deep cycle lead acid batteries, there is an inverse relationship between the discharge depth of the battery and the number of charging and discharging cycles it can perform, with an average discharge depth of about 50%.

Pros

In terms of battery performance, this type of lead acid battery is suitable for deep discharge. After deep discharge, the battery can recover to its capacity before discharge by charging. In addition, the deep cycle battery electrode plate has a thicker active electrode plate, a higher density active slurry, and a thicker membrane. Alloys used for deep cycle battery plates contain more antimony, and thicker battery plates can resist corrosion by extending the charging and discharging cycles.

Cons

Compared to traditional lead acid batteries, new technologies for deep cycle lead acid batteries have also become common in the same form as automotive lead acid batteries, with a significant price premium. At the same time, the capacity of deep cycle batteries is usually limited by the electrolyte capacity rather than the plate quality.

Application

The uses of deep cycle batteries include marine applications, especially on sailboats that lack power generation capacity, usually smaller ships. What’s more, it can also be used in off grid energy storage systems for solar or wind energy, especially in small installations in individual buildings or motor homes.

Cranking or Engine Starting Lead Acid Batteries

Source: Microsoft Bing

Introduction

Cranking lead acid batteries allow power to be sent to the engine when the switch is activated, so these batteries are also referred to as engine starting lead aicd batteries. To start the engines, a short and strong burst of energy must be sent from the battery. The larger the surface area of the electrode plate inside the battery, the easier it is for the battery to provide the necessary power. These plates increase the surface area and make the tool start as smoothly as possible.

Application

Cranking lead aicd batteries during discharge can cause irreversible damage to the battery plates, resulting in reduced performance and life of the battery, and in some cases lead to complete failure. However, the ability of cranking batteries to provide high vibration power in a short period of time is essential for starting a vehicle’s engine. Thus, batteries are mainly used for starting and lighting of automobiles, motorcycles, tractors, diesel engines, etc.

Link to CHANGINGTECH

How to Tell What Kind of Lead Acid Battery I Have?

Source: Veer

Read The Label

By introducing the main types of lead acid batteries, you must have a general understanding of lead acid batteries. The most direct way to find out which type of battery you purchase or own is to read the label on the battery.

Liquid or flooded lead acid batteries will have “lead acid”, “wet battery”, “flooded lead acid”, or “liquid lead acid” on the label. The gel filled lead acid battery will have “gel filled”. And AGM lead acid batteries will have “AGM “, “absorbent glass mat “, “sealed regulating valve” or “valve regulating ” on the label”.

Also look at the top of the battery. Flooded lead acid batteries have a cover or removable top, unless they have a label that says “sealed.”. Gel filled and AGM lead acid batteries have flat roofs, except for the positive and negative electrodes.

You can also find the manufacturer’s model number on the battery label. The manufacturer and manufacturer’s model name or number are on the label or embossed on the housing. Use it to obtain specifications from a battery store or manufacturer’s internet site to ensure the type of batteries.

Give It a Little Shake

Source: Veer

Shake the battery is also a good way to determine the type of lead acid battery. After shaking vigorously, the liquid lead acid battery will still swing when it remains stationary again. Even if the battery is sealed, the center of gravity of the liquid will continue to move for a moment. The gel filled and AGM lead acid batteries will stop swinging when they are still again after shaking with force.

Conclusion

Source: Unplash

Among the 4 types of lead acid batteries, AGM batteries have a life expectancy of 5 to 10 years, making them a good choice for low-cost batteries. For applications with a life expectancy of more than 10 years, gel lead acid batteries are a better choice. Therefore, there are choices made for different applications and environmental conditions. Not only should the battery life be evaluated, but also the key properties of the environment should be considered.

I hope this article can help you understand the types and resolution methods of lead acid batteries.

1) How often do I need to charge or "top off" my lead-acid batteries?

Maintaining your batteries is the key ingredient to ensuring that your battery bank reaches its designed life expectancy. What you may not know is that this typically does not happen on a partial state of charge on most batteries.  So, yes, your PV system may be charging during the day, but that does not mean that your bank is getting a full charge. The rule of thumb here is to ensure your bank is getting a full charge at least once a week.

2) How do I know if my battery bank is getting a full charge?

It is recommended that you install some type of battery monitor. This equipment helps you keep tabs on the state of charge of your battery bank, every day at a glance.  Many charge controllers and inverters are already equipped with this functionality, but if they are not there are third party devices that can fit the bill.

3) What if my battery bank is not getting at least one full charge per week? 

There are a few things you can do when you discover that your bank is not getting at least one full charge per week.  You can proactively decrease the amount of energy you are consuming by using some of your loads less.  If you find one or more of your loads is an energy hog you may consider replacing them with energy efficient models to help reduce your energy consumption. 

If those two options do not seem reasonable, consider adding a backup generator to your system.  The generator can help to pick up the slack and help maintain your battery bank by assisting the PV system in ensuring the battery bank is getting a full charge.  You may even consider expanding your PV system to make up for the lack of energy that is able to be harnessed and stored in the system.

4) If I connect my batteries to the inverter and/or charge controller, can I just turn the system on?

Default factory settings can harm your batteries.

Many inverters and charge controllers come with a factory default setting for voltage, battery type, and capacity.  Since this is almost always different per each individual system, carefully planning out your own settings is very important.  Consult those manuals!

Failure to properly set your battery bank to meet the demands of your PV system could result in overcharging or undercharging of batteries and over cycling of the bank.  Each leading to a shortened life for your battery bank.

5) My battery bank has served me well for some years now.  Can I replace my existing system with any type of new battery?

Unfortunately It’s not that simple. The settings on the inverter and/or charge controller must be considered first.  Before connecting the new battery bank first adjust the settings on your equipment.  These adjustments are made according to the type, voltage and capacity of the new batteries to be installed. The settings on your solar electronics are always done according to the type of battery installed.

Skipping over this critical step may shorten the lifetime of your new battery bank. You expect the bank to last 5-7 years, but may be disappointed when you get only two.

6) Can I mix new batteries into my old bank?

In a word, “don’t."

Many of our customers who currently have a battery bank later desire to expand their capacity or in some cases replace batteries that have failed for one reason or another.

Mixing different batteries is never a good idea. First of all, mixing batteries which are different in type, size, brand or voltage will not even work. Worse still, it can lead to battery bank failure.

If you were to mix a new battery to an old string or a new string to an older bank, the new batteries would reach their state of charge sooner than the older batteries.  This could lead to them boiling.  In terms of longevity, the new batteries will tend to cycle more often than the older batteries.  More cycles equate to a shorter life span for those batteries.  Typically this will not cause the older batteries to die first, but instead reduce the lifespan of the new one you have just installed. 

However, let’s say that we are working with identical batteries (exact type, size, brand and voltage), you can mix them up when the age difference between the old and new batteries is not more than 6 months. When adding new batteries to a battery bank that has been used for approximately 6 months or less, your new batteries will tend to adopt the age of your current battery bank.

7) When are batteries eligible for the ITC?

In short, for energy storage to qualify for the federal ITC the battery bank must be charged by the PV system onsite. If routinely less than 100% of the energy used to charge the battery bank comes from the grid and not the solar this will prorate the ITC incentive.  In other words, "if 90% of the storage charging energy is derived from solar panels, then the storage is only eligible for 90% of the ITC."  Particular attention must be paid to the energy used to charge the batteries in the first year.  "If the solar charging energy remains about 75% buts falls below the percentage established in the first year, then a proportional amount of the tax credit claimed in the first year must be recaptured."