Battery Basics

Cheaper Alternative To Century Jumper Battery Replacements (Or Any Battery For That Matter)

Save cost by reconditioning your batteries instead of replacing them, at a fraction of the price, with this proven method used by countless thousands in over 120 countries globally!

Having a portable jump starter like the Century Jumper 850 can come in handy especially in urgent situations when your car battery goes dead or lacks the power to crank the engine. The best thing about the Jumper 850 is that it has a 12V DC power output to power up any power-compatible devices you have.

The Century Jumper 850 replacement battery.

Replacing Century Jumper Batteries

The power supply in all Century portable jump starters come from sealed lead-acid (SLA) batteries encased within. The Jumper 850 specifically uses the 17Ah 12V ES Series SLA battery. At the date of this writing, the cost to replace the Century Jumper 850 battery is over US$100! But there’s a proven way to save on that cost.

The Proven & Cost Effective Alternative To Replacing Century Jumper Batteries

What most people don’t know is that all lead-acid batteries suffer from a degenerating process known as sulfation that kills batteries prematurely. Sulfation is the build-up of an insulating lead-acid crystal layer within the battery that ‘locks’ the needed battery life in an unusable, hard crystallized form. In other words, your battery’s lifespan will be cut in half!

The Infinitum Desulfator, seen here next to a pencil for size reference

The good news is that there is a remedy for sulfation, which is aptly called desulfation. Infinitum Desulfators have been in use since 2006 to successfully reverse sulfation, resulting in improved battery performance and optimized battery lifespan.

The robust build of this device ensures that you save not just on your first battery, but subsequent ones as well. You can also revive several batteries subsequently over a short period of time. But for the best results it is best to have a dedicated desulfator unit to work on each battery.

Infinitum Desulfators are so versatile, the same unit can be used for various applications, from cars, motorcycles, jetskis, forklifts to solar or wind power battery banks. 

Wai Tam, our customer in New York did just that and managed to successfully revive his Century Jumper 850 battery and moved on to optimize his solar batteries as well. Click here to watch Wai Tam’s battery recovery video.

Battery Basics

How To Test If A Desulfator Is Really Working

Testing the efficacy of your desulfator:

The best way to test the efficacy of our desulfators is to have the battery tested for CCA (Cold Cranking Amps) and milli Ohms (mΩ) before installation. You can either use a multimeter or a digital battery analyzer. Over time, you will notice an increase in the CCAs and a drop in the Ohms.

How long does it take to fully desulfate a battery?

  • 2 to 3 weeks when installed in a vehicle with daily city driving.
  • 2 to 3 days when installed with an external charger
  • 1 to 2 weeks with a solar or wind power

The above estimated durations are influenced by the following variables:

  • Level of sulfation
    A brand new battery will usually have a single digit milliohm reading while a heavily sulfated battery can have an Ohm reading up to a couple of hundred milliohms.
  • Amp hour rating of the battery
    Infinitum Desulfators are unique in that they are able to recondition even large forklift batteries without an issue. For road vehicles, 2 to 3 weeks is more than sufficient to fully desulfate a battery, the rest of the time, the desulfators work to prevent the accumulation of sulfation.
  • Duration of the charge
    The amount of effective sun and wind conditions affect the level of charge provided in a solar and wind power setup.

Battery Tip: When using an external charger, ensure that the charging amps on the charger is at least 10% of the battery’s Amp Hour (Ah) rating.

Why CCAs & Ohms?

The actual reading of a battery’s health is in its CCA (Cold Cranking Amps) or Ohms.

These two readings will contrast each other. CCAs measures the ability of a battery to start an engine. When sulfation occurs the build up of sulfate crystals will increase the resistance (Ohm) in the battery which in turn reduces the CCA.

Voltage readings indicate the state of charge for a battery, so in most cases, the voltage reading will remain high whenever the battery is fully charged. After all, you want to know a battery’s capacity to crank an engine, not its state of charge. So voltage is not always a true indication of the battery’s condition. 

What if I don’t see any results? Does that mean that the desulfator isn’t working?

There are instances even desulfators cannot recover because the failure or poor condition of the battery is not related to sulfation such as:

  • Natural wear & tear: old age, separators between plates decay, plate connectors corrode, etc.
  • Abuse – filling tap water instead of distilled water into the batteries.
  • Physical damage – any strong impact or dropping a battery
  • Lack of Maintenance – not filling water into the batteries, loose connectors.
  • Aging – batteries that are too aged will lose active material.
  • Crystallization of Lead Sulfate – 84% of batteries fail due to this (Battery Council International).

It can be that you are also using an amp rated charger that is too low

As the name suggests, desulfators can only recover sulfated batteries. Though there are several conditions where batteries cannot be recovered, 84% of premature battery failure is still due to sulfation, so it still makes sense to own an Infinitum desulfator as you can always use it on other batteries if one is unrecoverable. And due to the robust nature of the Infinitum, you can expect to reuse the device over several batteries throughout its service life. 

Battery Basics

How To Calculate A Battery Charge Time

Ever wondered how a lead-acid battery’s charge duration is calculated? This is the formula to calculate the charge duration:

Battery Charge Time = Battery Capacity / Charging Current
Time (Hours) = Amp Hours / Amps

So if you had a 100Ah battery charged with a 10A charger the duration of the charge would be calculated as in the example one below:

First Example:

Battery Amp Hour Rating / Charger Amp Rating:
100Ah / 10A
= 10 hours

In this example, for simplicity we have made 2 assumptions:

  1. The battery has a zero charge which never happens unless you have a dead battery.
  2. The battery charger has a charge efficiency of 100%. Usually, battery chargers have a charge efficiency of about 60 – 80%. (Our chargers have an efficiency above 80%).

Second Example:

Battery Amp Hour Rating / Charger Amp Rating
x Efficiency Loss
100Ah / 10A x (10/8)
= 10 hours x (10/8)
= 12.5 hours

In example two, we take the efficiency loss into consideration:

  1. Charger with an 80% efficiency.
  2. Charger Amp Rating 10A x (80/100) = 8A
Battery Basics

How Do Batteries Die?

When the active material in the plates of a battery can no longer sustain a discharge current, a battery “dies”. Normally a car (or starting) battery “ages” as the active positive plate material sheds (or flakes off) due to the normal expansion and contraction that occurs during the discharge and charge cycles. This causes a loss of plate capacity and brown sediment, called sludge or “mud,” that builds up in the bottom of the case and can short the plates of a cell out. This will kill the battery as soon as the short occurs. In hot climates, the following accelerate the “ageing” process contributing to battery failure:

  • positive grid growth,
  • positive grid metal corrosion,
  • negative grid shrinkage,
  • buckling of plates, or
  • loss of water deep discharges,
  • heat,
  • vibration,
  • fast charging, and
  • overcharging

Approximately 50% of premature car battery failures is caused by the loss of water for normal recharging charging due to the lack of maintenance, evaporation from high under hood heat, or overcharging. Positive grid growth and undercharging causing sulfation also cause premature failures. Normally well maintained and properly charged deep cycle batteries naturally die due to positive grid corrosion causing an open connection. The shedding of active material is an additional cause. If deep cycle battery is left discharged for a long period of time, dendrite shorts between the plates can occur when the battery is recharged. The low resistance bridge in the shorted cell will heat up and boil the electrolyte out of the cell causing high volumes of hydrogen and oxygen. That is why proper venting and ventilation is so important when recharging batteries. Approximately 85% of premature deep cycle and starting batteries failures that are not recharged on a regular basis is due to an accumulation of sulfation. 

Sulfation is caused when a battery’s State-of-Charge drops below 100% for long periods or undercharging. Hard lead sulfate crystals fill the pores and coats the plates. Recharging a sulfated battery is like trying to wash your hands with gloves on.

In a hot climate, the harshest environment for a battery, a Johnson Controls survey of junk batteries revealed that the average life of a car battery was 37 months. In a separate North American study by Battery Council International, the average life was 48 months. In a study by Interstate Batteries, the life expectancy in extreme heat was 30 months. If your car battery is more than three years old and you live in a hot climate, then your battery is probably living on borrowed time. Abnormally slow cranking, especially on a cold day, is another good indication that your battery is going bad. It should be externally recharged, surface charge removed, and load tested. Dead batteries almost always occur at the most inopportune times. You can easily spend the cost of a new battery or more for an emergency jump start, tow or taxi ride.

Most of the “defective” batteries returned to manufacturers during free replacement warranty periods are good. This strongly suggests that some sellers of new batteries do not know how to or fail to take the time to properly recharge and test batteries.

Source: Greg Darden | Image by Qfamily

Battery Basics

Did You Know You’re Unknowingly Killing Your Batteries?

“Up to 84% of batteries fail prematurely from sulfation”

– Battery Council International

Lead sulfation actually starts when you remove the charging voltage from a fully charged lead-acid battery. Though the lead sulfate crystals are converted back to lead during the normal charging cycle, the real question is, if all of the lead sulfate crystals are not turned back into lead, how long does it take before they become so hard that they can not be converted?

The answer is that varies–it could be weeks or months and depends on a number of factors such as the quality of the lead, temperature, plate chemistry, porosity, Depth-of-Discharge (DoD), electrolyte stratification, and so on.

How Sulfation Accumulate In Batteries

Crystallized sulfation that kills batteries prematurely

During the normal discharge process, lead and sulfur combine into soft lead sulfate crystals are formed in the pores and on the surfaces of the positive and negative plates inside a lead-acid battery. When a battery is left in a discharged condition, continually undercharged, or the electrolyte level is below the top of the plates or stratified, some of the soft lead sulfate re-crystallizes into hard lead sulfate. It cannot be reconverted during subsequent recharging. This creation of hard crystals is commonly called permanent or hard “sulfation”. When it is present, the battery shows a higher voltage than it’s true voltage; thus, fooling the voltage regulator into thinking that the battery is fully charged. This causes the charger to prematurely lower it’s output voltage or current, leaving the battery undercharged.

Sulfation accounts for approximately 84% of the lead-acid battery failures that are not used at least once per week. The longer sulfation occurs, the larger and harder the lead sulfate crystals become. The positive plates will be light brown and the negative plates will be dull, off white. These crystals lessen a battery’s capacity and ability to be recharged. This is because deep cycle and some starting batteries are typically used for short periods, vacations, weekend trips, etc., and then are stored the rest of the year to slowly self-discharge. Starting batteries are normally used several times a month, so sulfation rarely becomes a problem unless they are undercharged or the plates are not covered with electrolyte.

Permanent Sulfation

As a consequence of parasitic load and natural self-discharge, permanent sulfation occurs as the lead-acid battery discharges while in long term storage.

Parasitic load

Parasitic load is the constant electrical load present on a battery while it is installed in a vehicle even when the power is turned off.

The load is from the continuous operation of appliances, such as a clock, security system, maintenance of radio station presets, etc.). While disconnecting the negative battery cable will eliminate the parasitic load, it has no effect on the natural self-discharge of a car battery.

Self Discharge

Self -discharge is accelerated by temperature. For batteries that are over 77° F (25° C), the self-discharge rate doubles with a 18° F (10° C) rise in temperature.

Thus, sulfation can be a huge problem for lead-acid batteries which are:

  • not being used,
  • sitting on a dealer’s shelf, or
  • in a parked vehicle, especially in hot temperatures.

Image adapted from Qfamily

Battery Basics

How To Jump Start A Car

WARNING: Always wear protective spectacles whenever dealing with car batteries.

If done incorrectly, jumping a dead battery can be dangerous and financially risky. These procedures are ONLY for vehicles are that are both negatively grounded and the electrical system voltages are the SAME. These procedures would also apply to using emergency jump starters. DO NOT jump a frozen battery and ALWAYS connect POSITIVE to POSITIVE and NEGATIVE (-) to the ENGINE BLOCK or FRAME away from the dead starting battery. Reverse this rule to disconnect. The American Automobile Association (AAA) estimates that of the 275 million vehicles that will traveling in the U.S. during the Summer of 2003, 7.4 million (or 2.7%) will break down. Of that number, 1.3 million (or 17.7%) will require a battery jump to start their engine. The German automobile association (ADAC) estimates that their battery related service calls has increased from 21.7% per year in 1999 to 29.9% in 2004.

In cold weather, good quality jumper cables (or booster cables) with at least eight-gauge wire are necessary to provide enough current to the disabled vehicle to start the engine. Larger diameter, smaller gauge number wire is better because there is less voltage loss. Please check the owner’s manual for BOTH vehicles or jump starter BEFORE attempting to jump-start. Follow the manufacturers’ procedures, for example, some vehicles should not be running during a jump-start of a disabled one. However, starting the disabled vehicle with the good vehicle running can prevent having both vehicles disabled and provides a higher voltage to the starting motor of the disabled vehicle. Avoid the booster cable clamps touching each other or the POSITIVE clamp touching anything but the POSITIVE (+) post of the battery, because momentarily touching the block or frame can short the battery and cause extensive and costly damage.

Car Jump Starting Installation
  • If below freezing, ensure that the electrolyte is NOT frozen in the dead battery. If frozen, do NOT jump or boost the battery if the case is cracked or until the battery has been full thawed out, recharged, tested. When the electrolyte freezes, it expands which can damage the plates or plate separators, which can cause the plates to warp and short out. When the battery is frozen, the best solution is to substitute a fully charged battery for frozen one or tow the vehicle to a heated garage. With any completely dead battery, cell reversal can occur. Please Section 14.14. The electrolyte in a dead battery will freeze at approximately 20°F (-6.7°C). The freezing point of a battery is determined by the SoC and the higher it is, the lower the freezing temperature. If the battery has been sitting for several weeks and frozen, then the battery has probably sulfated as well. If the battery has been sitting for hours or a few days then the problem is either an excessive parasitic load like leaving the headlights on or a faulty charging system.
  • Without the vehicles touching, turn off all accessories, heaters and lights on both vehicles, especially electronic appliances, such as a radio or audio system and insure there is plenty of battery ventilation.
  • Start the vehicle with the good battery and let it run for at least two or three minutes at medium RPM to recharge it. Check the POSITIVE (+) and NEGATIVE (-) terminal markings on both batteries before proceeding.
  • Connect the POSITIVE booster cable (or jump starter) clamp (usually RED) to the POSITIVE (+) terminal post on the dead battery [Step 1 in the diagram above]. Connect the POSITIVE clamp on the other end of the booster cable to the POSITIVE (+) terminal post on the good starting battery [Step 2]. If the POSITIVE (+) battery terminal post is not accessible, the POSITIVE connection on the starter motor solenoid from the POSITIVE (+) terminal post of the battery could be used.
  • Connect the NEGATIVE booster cable clamp (usually BLACK) to the NEGATIVE (-) terminal on the good battery [Step 3]. Connect the NEGATIVE booster cable (or jump starter) clamp on the other end of the jumper cable to a clean, unpainted area on the engine block or frame on the disabled vehicle [Step 4] and at least 10 to 12 inches (25 to 30 cm) away from the battery. This arrangement is used because some sparking will occur and you want to keep sparks as far away from the battery as practical in order to prevent a battery explosion.
  • If using jumper cables, let the good vehicle continue to run at medium RPM for five minutes or more to allow the dead battery to receive some recharge, to warm its electrolyte, and reduce the load of the dead battery. If there is a bad cable connection, do not wiggle the cable clamps connected to the battery terminals because sparks will occur and a battery explosion might occur. To check connections, first disconnect the NEGATIVE clamp from the engine block or frame, check the other connections, and then reconnect the engine block or frame connection last.
  • If using jumper cables, some vehicle manufacturers recommend that you turn off the engine of the good vehicle to protect it’s charging system prior to starting the disabled vehicle. Check the owner’s manual; otherwise, leave the engine running so you can avoid being stranded should you not be able to restart the good vehicle and increase the voltage to the disabled vehicle’s starter motor.
  • If using jumper cables, start the disabled vehicle and allow it to run at high idle. If the vehicle does not start the first time, recheck the connections, wait a few minutes, and try again.
  • Disconnect the jumper or jump starter cables in the REVERSE order, starting with the NEGATIVE clamp on the engine block or frame of the disabled vehicle to minimize the possibility of an explosion. Allow the engine on the disabled car to run until the engine come to full operating temperature before driving and continue to run until you reach your final destination, because stopping the engine might require another jump start. Also, keep all unnecessary electrical accessories off to relieve the load on the charging system and allow it to add charge to the battery.
  • As soon as possible and at room temperature, fully recharge the dead battery with an external “smart” or “automatic” battery charger matched to the battery type, remove the surface charge and load test the battery and charging system to determine if any latent or permanent damage has occurred as a result of the deep discharge. This is especially important if you had a frozen battery or jump started a sealed wet Maintenance Free (Ca/Ca) battery. A vehicle’s charging system is not designed to recharge a dead battery and could overheat and be damaged (bad diodes or burned stator) doing so or the battery could be undercharged and loose capacity.

In the event that the jumper or jump starter cables were REVERSED and there is no power to all or part of the vehicle, test the fusible links, fuses, circuit breakers, battery, charging system and emissions computer and, if bad, reset or replace. Their locations and values should be shown in the vehicle’s Owner’s Manual. If replacing the faulty parts do not repair the electrical system, having it repaired by a good auto electric repair shop is highly recommended.


Battery Basics Dead Battery Recovery

How Can I Tell If My Battery Has Permanent Sulfation?

Chances are that your battery has some permanent sulfation, if it will not “take” or “hold” a charge and exhibits one or more of the following conditions:

  • If your wet (flooded) Standard (Sb/Sb) or wet (flooded) Low Maintenance (Sb/Ca) battery has been not been recharged for over three months, especially if the temperature in the storage area was consistently over 77° F (25° C). [Six months for wet “Maintenance Free” (Ca/Ca) or one year for AGM (Ca/Ca) or Gel Cell (Ca/Ca)VRLA.]
  • While recharging in a well-ventilated area, the ammeter does not drop to below 2% (C/50) of the expected time to recharge the battery and the battery is warm or hot. For example, if you have a fully discharged 50 Amp Hour battery and a ten amp charger, a discharged battery should be fully charged within 10 hours (2 x 50 AH / 10 amps = 10 hours).
  • If the Specific Gravity is low in all cells after the battery has been on a charger for a long time.
  • If the temperature compensated absorption charging voltage is correct and the battery is gassing or boiling excessively.
  • Poor performance or low capacity.
  • When the SoC (State-of-Charge) measured by a hydrometer, which is more accurate, does not materially agree with the SoC measured by a digital voltmeter.

Source: Greg Darden. Image by Charles Williams.

Battery Basics

Types Of Deep Cycle Batteries

Unlike batteries used to start engines, deep cycle batteries are designed to store power. They have fewer and thicker lead plates as compared to starter batteries. Starter batteries are designed to provide a sudden surge of power needed to crank an engine, so there are more lead plates within these batteries and they are thinner, providing a larger surface area. 

Deep cycle batteries are often used in marine vessels, RVs, motor homes or caravans to provide power to run electrical equipment and appliances. So you would need a battery that would store a large quantity of power, to discharge deeply, and to recharge over and over again.

There are three basic types of deep cycle batteries.

  1. Lead Acid Flooded Cell
  2. Gel Cell
  3. AGM (Absorbed Glass Mat)

Lead Acid Flooded Cell

Lead Acid Flooded Cell batteries are the typical batteries that you see in most deep cycle applications. They are available in several sizes, in both 12v and 6v. They have very thick lead plates submerged in an acid solution (electrolyte). The majority of RV’s or caravans use this type of battery.

Many RV’s have two or more 6-volt batteries, wired in series and parallel to create a 12-volt battery bank. Golf Cart batteries are the primary example, and Trojan brand size T-105 is the industry standard.  

  • Advantages: Inexpensive, durable, powerful, widely available.
  • Disadvantages: Produce corrosive and flammable gasses when charging, so they must be in a vented compartment. Can spill and are corrosive. Must be checked periodically and water must be added to them because small amounts boil away during charging.
  • A great choice for most applications.

Gel Cell Batteries

Gel Cell Batteries are similar to Flooded Cell batteries, except the electrolyte is gelled. For this reason, they require little maintenance and rarely if ever emit gasses.

  • Advantages: Low maintenance, no venting of gasses, somewhat greater capacity than standard flooded cells.
  • Disadvantages: Expensive, slow to charge, can be easily damaged by improper charging – even once.
  • Not Recommended: They’re just too picky and easy to damage, also charge rates are too slow.

AGM (Absorbed Glass Mat) 

AGM (Absorbed Glass Mat) batteries have a glass mat material between the plates and the electrolyte is absorbed into this glass mat. This makes them “spill-proof” and they’re the only battery that can be shipped via UPS or FedEx. Being spill-proof also gives them advantages in RV and marine use.

  • Advantages: Low maintenance, no venting of gasses, they will take a charge faster than other batteries (if you have a big enough charger), can be installed on their side if necessary, can be installed in un-vented compartment**, can be installed in tight fit area because you don’t have to check water level, etc.
  • Disadvantages: Expensive. Can be damaged by excessive float voltage, but MUCH more durable than Gels.
  • Recommended for convenience anytime cost isn’t a concern. Also for special applications in tight fit areas

All deep cycle batteries regardless of type suffer a degenerative process also known as Sulfation. This process can be reversed saving your battery (in most cases even junked or ‘dead’ batteries), with the Infinitum Desulfator. 

This article has been selected or written for the benefit of our customers and visitors. Information found in these articles are of general nature and can not be applied universally. For this reason, we strongly advise anyone seeking advice or information to find a professional who can assist with your specific situation.

Battery Basics

Is Specific Gravity A True Indicator Of Battery Health

Due to its low cost, hydrometers are often used to measure the specific gravity or the concentration of the sulfuric acid in a battery. The specific gravity measurement reflects the state of charge of a battery. In other words, the higher the charge level of a battery, the greater will be the specific gravity reading. Over time, all acid-based batteries will experience a depletion inactive material, which is normal. The more pronounced the depletion, the lower the specific gravity will be in a fully charged battery. As batteries age the capacity to hold a charge deteriorates. Therefore, an aged battery even after going through a process of desulfation, will still show a lower specific gravity than a new battery.

A more accurate diagnosis of your battery health

A battery measuring at 755 CCAs

In internal combustion vehicles, batteries are essentially used to crank an engine and once the engine is running, the alternator kicks in to charge the battery and to drive the electronics in the car. So instead of measuring a battery’s specific gravity, it’s actually more relevant to measure the CCAs or cold cranking amps of the battery. After all, you don’t need to know the charge level of the battery but rather how well it will crank your vehicle.

Why specific gravity is a poor measurement of a battery’s health

Cold Cranking Amps is a rating used in the battery industry to define a battery’s ability to start an engine in cold temperatures. The rating is the number of amps a new, fully charged battery can deliver at 0° Fahrenheit for 30 seconds, while maintaining a voltage of at least 7.2 volts, for a 12 volt battery. The higher the CCA rating, the greater the starting power of the battery.

To accurately measure the health of car batteries, buy our digital battery analyzer or find out more about optimizing battery life span with our battery desulfators.

What is CCA or cold cranking amps?

1. Specific gravity does not show the battery’s state of performance or lifespan
​Specific gravity is an inaccurate measurement of a battery’s performance because it varies according to the battery’s state of charge. It doesn’t show how much more lifespan is left in the battery.

2. Specific gravity only shows you the battery’s state of charge
Specific gravity is actually a poor indicator of the battery’s performance as it changes depending of the state of charge of the battery, and it doesn’t actually tell you how much more lifespan you have left in your battery. In addition, the maximum specific gravity varies from battery to battery. For instance, certain batteries only have a maximum specific gravity of 1.255 to 1.260 while Maintenance-Free batteries can go up to 1.280.

Battery Basics

Anatomy Of A Lead Acid Battery


Lead-acid batteries contain a diluted sulfuric acid electrolyte and positive and negative electrodes, in the form of several plates. Since the plates are made of lead or lead-derived materials, this type of battery is often called a lead-acid battery. 

A battery is separated into several cells (usually six in the case of automobile batteries), and in each cell there are several battery elements, all bathed in the electrolyte solution.

Lead Acid Battery Anatomy