Can the Lead-acid Battery Compete in Modern Times?
The answer is YES. Lead-acid is the oldest rechargeable battery in existence. Invented by the French physician Gaston Planté in 1859, lead-acid was the first rechargeable battery for commercial use. 150 years later, we still have no cost-effective alternatives for cars, wheelchairs, scooters, golf carts and UPS systems. The lead-acid battery has retained a market share in applications where newer battery chemistries would either be too expensive.
Lead-acid does not lend itself to fast charging. Typical charge time is 8 to 16 hours. A periodic fully saturated charge is essential to prevent sulfation and the battery must always be stored in a charged state. Leaving the battery in a discharged condition causes sulfation and a recharge may not be possible.
Finding the ideal charge voltage limit is critical. A high voltage (above 2.40V/cell) produces good battery performance but shortens the service life due to grid corrosion on the positive plate. A low voltage limit is subject to sulfation on the negative plate. Leaving the battery on float charge for a prolonged time does not cause damage.
Lead-acid does not like deep cycling. A full discharge causes extra strain and each cycle robs the battery of some service life. This wear-down characteristic also applies to other battery chemistries in varying degrees. To prevent the battery from being stressed through repetitive deep discharge, a larger battery is recommended. Lead-acid is inexpensive but the operational costs can be higher than a nickel-based system if repetitive full cycles are required.
Depending on the depth of discharge and operating temperature, the sealed lead-acid provides 200 to 300 discharge/charge cycles. The primary reason for its relatively short cycle life is grid corrosion of the positive electrode, depletion of the active material and expansion of the positive plates. These changes are most prevalent at higher operating temperatures. Cycling does not prevent or reverse the trend.
The lead-acid battery has one of the lowest energy densities, making it unsuitable for portable devices. In addition, the performance at low temperatures is marginal. The self-discharge is about 40% per year, one of the best on rechargeable batteries. In comparison, nickel-cadmium self-discharges this amount in three months. The high lead content makes the lead-acid environmentally unfriendly.
Plate thickness
The service life of a lead-acid battery can, in part, be measured by the thickness of the positive plates. The thicker the plates, the longer the life will be. During charging and discharging, the lead on the plates gets gradually eaten away and the sediment falls to the bottom. The weight of a battery is a good indication of the lead content and the life expectancy.
The plates of automotive starter batteries are about 0.040" (1mm) thick, while the typical golf cart battery will have plates that are between 0.07-0.11" (1.8- 2.8mm) thick. Forklift batteries may have plates that exceed 0.250" (6mm). Most industrial flooded deep-cycle batteries use lead-antimony plates. This improves the plate life but increases gassing and water loss.
Sealed lead-acid
During the mid 1970s, researchers developed a maintenance-free lead-acid battery that can operate in any position. The liquid electrolyte is gelled into moistened separators and the enclosure is sealed. Safety valves allow venting during charge, discharge and atmospheric pressure changes.
Driven by different market needs, two lead-acid systems emerged: The small sealed lead-acid (SLA), also known under the brand name of Gelcell, and the larger Valve-regulated-lead-acid (VRLA). Both batteries are similar. Engineers may argue that the word 'sealed lead-acid' is a misnomer because no rechargeable battery can be totally sealed.
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Unlike the flooded lead-acid battery, both SLA and VRLA are designed with a low over-voltage potential to prohibit the battery from reaching its gas-generating potential during charge because excess charging would cause gassing and water depletion. Consequently, these batteries can never be charged to their full potential. To reduce dry-out, sealed lead-acid batteries use lead-calcium instead of the lead-antimony. The optimum operating temperature for the lead-acid battery is 25*C (77*F). Elevated temperature reduces longevity. As a guideline, every 8?C (15*F) rise in temperature will cut the battery life in half. A VRLA, which would last for 10 years at 25*C (77*F), will only be good for 5 years if operated at 33*C (95*F). Theoretically the same battery would last a little more than one year at a desert temperature of 42*C (107*F). |
 Figure 1: Sealed lead-acid battery |
The sealed lead-acid battery is rated at a 5-hour (0.2) and 20-hour (0.05C) discharge. Longer discharge times produce higher capacity readings because of lower losses. The lead-acid performs well on high load currents.
Absorbed Glass Mat Batteries (AGM)
The AGM is a newer type sealed lead-acid that uses absorbed glass mats between the plates. It is sealed, maintenance-free and the plates are rigidly mounted to withstand extensive shock and vibration. Nearly all AGM batteries are recombinant, meaning they can recombine 99% of the oxygen and hydrogen. There is almost no water is loss.
The charging voltages are the same as for other lead-acid batteries. Even under severe overcharge conditions, hydrogen emission is below the 4% specified for aircraft and enclosed spaces. The low self-discharge of 1-3% per month allows long storage before recharging. The AGM costs twice that of the flooded version of the same capacity. Because of durability, German high performance cars use AGM batteries in favor of the flooded type.
Advantages
- Inexpensive and simple to manufacture.
- Mature, reliable and well-understood technology - when used correctly, lead-acid is durable and provides dependable service.
- The self-discharge is among the lowest of rechargeable battery systems.
- Capable of high discharge rates.
Limitations
- Low energy density - poor weight-to-energy ratio limits use to stationary and wheeled applications.
- Cannot be stored in a discharged condition - the cell voltage should never drop below 2.10V.
- Allows only a limited number of full discharge cycles - well suited for standby applications that require only occasional deep discharges.
- lead content and electrolyte make the battery environmentally unfriendly.
- Transportation restrictions on flooded lead acid - there are environmental concerns regarding spillage.
- Thermal runaway can occur if improperly charged.
Comments
SLA = Sealed Lead-Acid
So many people think they are ‘dry cells’ but the truth is they still have acid inside the battery, it just cant leak because of the ‘Sealed’ part of the name.
My casual experience with deep cycle and starting batteries is that the deep cycle seem to have a longer life even if the deep cycle is experiencing some discharge as in the case on my boat trolling motor battery. Furthermore, when I put deep cycle batteries in my cars it seems like they last longer than the official recommended high current starting batteries. I wonder if the thin plates inherent in starting batteries results in them just have a shorter life? To be fair about this, I live in Texas where it hardly ever gets cold so my vehicles just don’t need the CCA that’s needed somewhere like Minessota.
Deep cycle batteries do not have high cca. But in your case where it is not cold this probably doesnt matter. Deep cycle batteries are also more expensive
This stuff is so good. Good info.
http://tinyurl.com/centurion-bilaps
BILAPS is the acronym for Bipolar Lead-Acid Power Source. In the 6th framework programme “BILAPS research project ENK6-CT-2001-00544”, supported by the European Union, CENTURION AKKU was responsible for the development of the active mass and for the assembly process.
The objective of the project was the development of a low-cost high power battery for applications in hybrid vehicles and in 42 Volt systems.
The main advantage of the bipolar battery is the high capacity it provides given its low weight. This low weight is possible thanks to the exclusion of all the lead components that do not contribute to the delivery of current. Examples include grids and cell connectors. The structure of the bipolar battery can be compared to that of a fuel cell: the stacking of cells provides the compression for the mechanical rigidity. By using only current-providing lead, weight is reduced by about 50%. This doubles the specific power (Watt per kilo)!
The advantages of a bipolar lead-acid battery compared to other technologies such as Lithium-Ion, Lithium-Polymer or Nickel-metal-hydride are:
- the relatively low price of lead,
- the proven recycling system for lead batteries (>95% for starter batteries and 100% for industrial batteries),
- low-cost production technology in mass production.
Objectives:
Specific power > 500 W/kg (power assist 30 s)
Life 400 - 600 equivalent deep cycles (12,000 - 18,000 Ah throughput for a 30 Ah system)
My name is Khawaja Ayaz. Birth date 1st May 1985. I have done Bachelor of Technology in Electrical. Wording in Pakistan Accumulators Pvt Ltd (Manufacturers of Lead Acid Battery) as a Claim Executive.
This article contains easy, effective and advance knowledge, I really like this.
U must send updates on this topic regularly via email.
Regards;
Khawaja Ayaz
Can the lead-acid battery compete in modern times? The only reason we still continue to use this technology is because it’s cheap- it’s been around for long time. most simple application that don’t require heavy power demand- car batteries, ups, will suffice with lead acid battery- anything beyond that like an EV forget it. but truth is- if you really wanted to you could get a cheap li-ion battery and it would work just as well and last way longer- i’ve seen many video’s of people using a123 for car batteries or to start a truck engine.
Very helpful information. Is it possible to rejuvenate a lead-acid battery that has been stored for a year and is thoroughly discharged? There are two batteries for an electric wheelchair that are in this state.
Your organization spreading unique and advance knowledge. This Practice remain continue through mail.
Regards;
Khawaja Ayaz
I know the sulfation tank ( by lead acid proces)
I am sure lead acid battery will compete in the modern time due to its usage for over 140 years.
The lead acid battery has a recycle rate of >95%. The Lithium battery has a recycle rate of <5%. Which is environmentally unfriendly again?
LEOCH International - a lead acid battery manufacturer,
Sanyo eneloop batteries are 2900mah and come pre charged. They also hold 85% of their charge after being stored for 12 months. They can be recharged up to 1500 times while other brands brag about 500 cycles. I sell and recommend them to everyone, and I use them myself for everything
Several UB5-6S, used in squared-off flashlights w/ halogen bulbs, suddenly failed. They seemed to charge to nearly 6V, but drop to 0.2V when the small bulbs are switched on. With two of them, leaving them upside down in the flishlights may have been a problem. However a 3rd was upright in a closet, still over 4V, and exhibits the same problem.
In this site some valuable information is missing, i want to share with all of you.
This information is about First true functional battery invented.
n 1800, Alessandro Volta of Italy built the voltaic pile and discovered the first practical method of generating electricity. Count Volta also made discoveries in electrostatics, meteorology and pneumatics. His most famous invention, however, is the first battery.
Alessandro Volta - Voltaic Pile
In 1800 Volta invented the first true battery which came to be known as the Voltaic Pile. The Voltaic Pile consisted of pairs of copper and zinc discs piled on top of each other, separated by a layer of cloth or cardboard soaked in brine (i.e. the electrolyte). Constructed of alternating discs of zinc and copper, with pieces of cardboard soaked in brine between the metals, the voltaic pile produced electrical current. The metallic conducting arc was used to carry the electricity over a greater distance. Alessandro Volta’s voltaic pile was the first battery that produced a reliable, steady current of electricity.
History of Battery Development
1600 Gilbert (England) Establishment electrochemistry study
1791 Galvani (Italy) Discovery of ‘animal electricity’
1800 Volta (Italy) Invention of the voltaic cell
1802 Cruickshank (England) First electric battery capable of mass production
1820 Ampère (France) Electricity through magnetism
1833 Faraday (England) Announcement of Faraday’s Law
1836 Daniell (England) Invention of the Daniell cell
1859 Planté (France) Invention of the lead acid battery
1868 Leclanché (France) Invention of the Leclanché cell
1888 Gassner (USA) Completion of the dry cell
1899 Jungner (Sweden) Invention of the nickel-cadmium battery
1901 Edison (USA) Invention of the nickel-iron battery
1932 Shlecht & Ackermann (Germany) Invention of the sintered pole plate
1947 Neumann (France) Successfully sealing the nickel-cadmium battery
Mid 1960 Union Carbide (USA) Development of primary alkaline battery
Mid 1970 Development of valve regulated lead acid battery
1990 Commercialization nickel-metal hydride battery
1992 Kordesch (Canada) Commercialization reusable alkaline battery
1999 Commercialization lithium-ion polymer
2001 Anticipated volume production of proton exchange membrane fuel cell
specification of Iron & Chlorine content on the battery separator glassmat
“A better battery for start-stop”, 26Sep11: www.sae.org/mags/aei/10199
super
sir,it is very usefullfor me.nowdays,i have used ‘sla’ battery also.thank u.