What should be the specific gravity of lead-acid battery?

A fully charged lead acid battery cell has voltage and specific gravity, 2.2 V and 1.250 respectively, and this cell is normally allowed to be discharged till the corresponding values become 1.8 V and 1.1 respectively.

What does the specific gravity of a battery tell us?





The most accurate and direct way to test the state of charge of a battery cell is to determine the specific gravity of the battery electrolyte. The higher the specific gravity of the electrolyte the higher the state of charge.

What is the specific gravity of a discharged battery?

A battery hydrometer is used to read the relative density (specific gravity) of the sulfuric acid in the electrolyte and check the charge of the battery.. The density varies from about 1.28 in a fully charged battery to 1.15 in a discharged battery..

Does lead-acid battery degrade?

All rechargeable batteries degrade over time. Lead acid and sealed lead acid batteries are no exception.

What is the specific gravity of a fully charged 12V battery?

from 1.280 to 1.300





The specific gravity of the electrolyte in a fully charged cell should be from 1.280 to 1.300. If it varies more than 10 points above or below these values, adjust it by drawing off some of the electrolyte with a hydrometer and adding water to lower the gravity, or 1.400 acid to raise the gravity.

What does a battery hydrometer tell you?

A hydrometer is used to determine the state of charge of each cell of a battery. The hydrometer will determine the cells specific gravity of electrolyte (its weight compared to water). A hydrometer is a bulb or tear drop syringe which will extract electrolyte from the cell.

What happens if specific gravity of battery is low?

Low battery gravity will reduce the effectiveness of the battery in terms of its charge capacity and the extent of its draining. However, you also need to understand that high gravity will result in battery wear and destruction of its plates and so you should maintain your battery gravity between 1.180-1.240.

How high should the electrolyte level be in a properly serviced lead-acid battery?

Figure 3-20 illustrates the correct electrolyte level for a lead-acid battery. Remember, always add distilled water only, never electrolyte. The proper level should be above the plates and about 1 in. below the top of the battery.

Do lead acid batteries lose capacity over time?



Over time, battery capacity degrades due to sulfation of the battery and shedding of active material.

At what voltage is a lead acid battery discharged?

Lead acid discharges to 1.75V/cell; nickel-based system to 1.0V/cell; and most Li-ion to 3.0V/cell. At this level, roughly 95 percent of the energy is spent, and the voltage would drop rapidly if the discharge were to continue.

What is the lifespan of a lead acid battery?

Sealed lead acid batteries can have a design life of anywhere from 3 – 5 years all the way up to 12+ years depending on the manufacturing process of the battery. There are many factors that affect the service life of the battery including temperature, for more information please view our technical manual.

How do you refresh a lead acid battery?



Quote from the video:
Quote from Youtube video: I begin by adding two milliliter of 30 percent sulfuric acid solution into each cell. Then I add distilled water all the way up to the top of the plate.

How do you bring a dead lead acid battery back to life?

Attach a battery trickle charger or a computerized smart charger to your old lead acid battery, and allow charging continuously for about a week to 10 days. The extremely slow charging rates dissolve the de-sulphation that kills the battery, and revives it back to being able to hold a usable charge.

How often should lead acid batteries be replaced?

A deep-cycle battery delivers 100–200 cycles before a gradual decline begins. Replacement should occur when the capacity drops to 70 or 80 percent. Some applications allow lower capacity thresholds but the time for retirement should never fall below 50 percent as aging may hasten once past the prime.

Does Desulfating a battery work?

If you own a battery desulfator, you can lengthen its lifespan and enjoy even more miles on the road. Plug your car battery into a desulfator and you’ll enhance its effectiveness even as it ages.