Batteries Flashcards
What materials make up the construction of a Lead Acid Battery?
-Plates
• positive plates ( PbO² )
• negative plates ( Pb )
-Separators
-Cell elements
-Electrolytes
-Cells
-Battery case
What is a deep cycle battery
-Fewer but heavier plates than an automotive battery
- Designed for lower current discharge over a longer time.
- Battery life can be greatly extended if the depth of each discharge cycle is kept above 50%.
Marine Battery
- Has some characteristics of automotive and deep cycle batteries.
- Not a suitable replacement for deep cycle batteries on an RV
- Not a suitable replacement for starting batteries in cold climates.
Battery install
• Must be securely attached
• Compartments must be vapor tight to the interior and vented to the exterior
• Circuit protection must not be more than 5 feet from the battery and must be within 18.5 inches from where the cable enters the RV.
Battery storage
• Store fully charge
• Disconnect any loads.
• Store in a cool, dry area.
• Recharge periodically… at least every 1 to 2 months.
Battery maintenance
•Always disconnect the ground cable first and reconnect last?
• Inspect cells for correct electrolyte level.
• Fill to the bottom of the inspection hole with distilled water.
• Never attempt to charge a frozen battery.
• Never charge a battery that has the electrolyte level below the top of the plates
Battery installation
• Never mix batteries of different voltage amp hour rating or age
• Batteries connected in parallel, will increase amperage and voltage will not change.
• Batteries connected in series will increase the voltage, and amperage will not change.
Battery principles
•EMF ( Voltage ) is produced from an acid acting on 2 different materials.
• In the case of lead acid batteries, the electrolyte is acid-based, and the cell plates are 2 different types of lead materials.
• When discharging, So4 ( sulfate ) moves to both plates from PbSo4 ( lead sulfate ), the O² ( oxygen), and H² ( hydrogen) combine to form H²O ( Water )
• Fully charged battery
- Positive plates: PbO2 ( lead peroxide)
- Negative plates: Pb ( sponge lead )
- Electrolyte: 36% H2SO4 ( sulfuric acid)
64% H²O ( water )
• Cell plates are connected in parallel. Positive plates together and negative plates together.
Automotive battery
• Sometimes called the “starting battery” or in the RV industry, the “chassis” battery.
• Has more and thinner plates than a deep cycle battery.
• Design to supply high current over a short period
Battery testing
• Voltage should be approximately 2.13 Volts / cell
• 12 volt battery: 6 cells times 2.13 Volts =12.78 Volts
• 12.0 Volts Considered a dead battery
• 6 volt battery: three cells x 2.13 volts = 6.39 volts
Limitations of lithium-ion batteries.
• They have a tendency to overheat. And can be damaged at high voltages.
• Most lithium-ion electrolytes are highly flammable, so damaged batteries can experience thermal runaway and combustion.
• Because of the risks associated with lithium-ion batteries, a number of shipping companies refused to perform bulk shipments of batteries by plane.
• Lithium-ion batteries require safety mechanismsk to limit voltage and internal pressures, which can increase weight and limit performance in some cases.
• Lithium-ion batteries are also subject to aging. Meaning that they can lose capacity and frequently fail after a number of years.
• Degradation, cost, and safety make Lithium-ion batteries a poor fit for grid scale energy storage.
• Despite the high energy density of lithium-ion compared to other kinds of batteries.
• They are still around a 100 times less energy dense than gasoline, which contains 12,700 Wh/kg by mass or 8760 Wh/L by volume.
Advantages of lithium-ion batteries.
• High energy density.
• Lightweight
• Long lifespans
• Good long term performance
• Temperature tolerant
• Low self discharge
• Fast charge times
• Customizable technology
What is the purpose of an RV battery?
To provide power for the various electrical components in an RV when it is not connected to shore power.
What is the difference between a starting battery and a deep cycle battery?
Starting batteries are designed to provide a quick burst of energy to start the engine, while deep cycle batteries are designed to provide a steady amount of power over a longer period of time.
What is the typical voltage output of an RV battery?
12 volts
What are the three main types of RV batteries?
Lead-acid, AGM (Absorbent Glass Mat), and Lithium-ion
What is the advantage of AGM batteries over traditional lead-acid batteries?
AGM batteries are maintenance-free, can be mounted in any position, and have a longer lifespan.
What is the advantage of Lithium-ion batteries over lead-acid batteries?
Lithium-ion batteries are lighter, have a higher energy density, and can be discharged more deeply without damage.
True or False: It is safe to mix different types of batteries in an RV electrical system.
False
What is the recommended way to charge an RV battery?
Using a dedicated RV battery charger or a solar panel system.
What is the purpose of a battery isolator in an RV?
To prevent the RV’s starter battery from being drained when using the house battery.
What is the typical lifespan of an RV battery?
3-5 years
What is the self-discharge rate of a lead-acid battery compared to a lithium-ion battery?
Lead-acid batteries have a higher self-discharge rate than lithium-ion batteries.
Fill in the blank: AGM stands for ________.
Absorbent Glass Mat
