Car battery care

Testing a Battery an the BLS

  1. Measure and record the battery voltage. It should measure approximately 12.7 volts. (This is assuming you are starting
    with a functioning battery.)
  2. Measure and record the specific gravity of each cell in the battery. (If you have a maintenance free battery, you are out of
    luck, you can’t do this test.) The specific gravity of a new battery should be 1.300. If your battery is two years old, the
    specific gravity may be around 1.150 – 1.200. A battery in poor condition that is about to fail may be as low as 1.100.
  3. Record the date of this test. Save the report for later reference.
  4. Every 14 days, repeat steps 1,2 and 3. You will see the specific gravity gradually increase until it reaches that of a
    new battery.

12 Volt Battery

Digital Voltmeter Open Circuit Voltage ApproximateState-of-Charge at 80°F (26.7°C) Hydrometer AverageCell Specific Gravity Electrolyte Freeze Point
12.65 100% 1.265 -77°F (-67°C)
12.45 75% 1.225 -35°F (-37°C)
12.24 50% 1.190 -10°F (-23°C)
12.06 25% 1.155 15°F (-9°C)
11.89 or less DISCHARGED 1.120 or less 20°F (-7°C)

Testing for a Bad Battery

  1. Step 1: Physical & Mechanical Inspection
  2. Step 2: Preparing the Tests
  3. Step 3: Testing for a Short Cell
  4. Step 4: Testing for an Open Cell in a Flooded/Wet cell battery


forum: Reconditioning Lead Acid Batteries with Epsom salt

“”Before it would only take about a 1Ah charge, now takes about a 3Ah charge.”” there is one clue.

So try this for a Guess.

Because the resistance in the battery changed, so the voltage taper that the normal charger does current would go up, it would heat the battery more, and continue to hit the plates, doing basically the same thing the overcharging, pulse overcharging, or “desulfation” does within the parameters that the usual car charger work under.

The usual car charger:
Using a ac-dc transformer, and specific peak voltages after bridge rectifying, the usual car charger lightens up on the charge as it reaches the end. The old battery with encrusted plates is high resistance. the addition of epsom salts shorts out the internals of the battery some, and decreases the resistance. the decreased resistance get the usual car charger to continue charging, just like overcharging and “desulphation” algorithms do.
The car alternator also relys on cramming a specific voltage potential in, and the battery voltage increasing, therby slowing down the rate of charge as the battery is more charged. so it acts pretty much the same way.

IF that was what was occurring, a person risks increased wear and tear on the vehicles electrical system.
I have found more than once, that trying to use a battery that basically sucks (power) because it has bad cell and all, has cause me to have to replace more of the electrical charging system, like alternator, and charge regulator, on the older cars.

epsom salts is magnesium sulfate, basically metals that are water soluable, what is occuring is adding minerals to the electrolyte. generally this is concidered a bad thing like using tap water, instead of distilled. But whatever works, it could allow for overcharging via chargers that do not do that normally.

if a lab did an analisis they would probably discover nothing, because it probably keys on the specific way that a consumer car charger operates, and a lab would use a bench power supply instead, to have “control” of the current going on for testing.
Anyone who attempted to do a “de-sulphation” with high overcharge, or pulse overcharge probably would be doing the same thing, with slightly less damage, and achieve much the same results.
Also if it was tested in the lab, the self-discharge of the battery might be measured. Depending on a battery that had been through this method, to hold capacity , and capacity over time might show that it can start a car, but not be reliable source of long term energy storage.

At any rate, unless you pull out the lead, melt it back into position there would be nothing long term about any of the methods, they all work for a bit, and the eroded decaying plates still exist, along with the piles of decaying and eroded materials that float down below the plates. Yup, I tried to recover a lot of LA stuff back in time, lots of the stuff that was discarded was usable, and could be coaxed, but never lasted long. <mentione there.

one budding chemist says the chemical reaction is magnesium sulfate and the water with an electrical energy produces sulferic acid and magnesium oxide.

more cheap trix PVA:
“”The authors claim that (1) the PVA prevents the diffusion of Pb, (lead), ions into the electrolyte. They say this reduces the generation of PbSO4, (lead sulfate), hence (2) helps to reduce sulfation. I have done research in the exact same area. My tests imply that (1) is accurate and (2) is an inaccurate guess.
The 12V batteries were charged to 17 volts, which is way above normal. The authors pointed out that the normal charging voltage is 14V. They said the higher voltage is necessary when additives are put in. Hello! How is a normal automobile electrical system going to cope with this?””

the better question becomes if the battery was charged high “overcharged” then some of that junk on the plates will fall off, or go back to the plates or the solution. it wouldnt mater if you put urine in 🙂 its the slamming the power in which reverses the chemical reactions.
discusses that there might be better short term fix chemicals to use. And also discusses cleaning the plates and making alkaline Lead battery. <–HKJs DMM guide.


Chemistry explanation:

The type of lead sulfate crystals that form on a neglected battery electrode are very insoluble in water. Magnesium sulfate on the other hand is very soluble in water. From a practical standpoint, all chemical reactions are reversible. If magnesium sulfate and lead sulfate are placed near each other in solution, the magnesium and lead can switch places. Now, part of the big crystal is magnesium sulfate, which is both soluble in water and not too happy in the crystal, and so it detaches and floats around in the battery. Your crystal size has now decreased. Repeat this a few sextillion times, and the lead sulfate that was blocking the electrode is gone (as well as putting the lead sulfate back into solution where it is useful). Note however that the addition of magnesium sulfate will slightly lower the voltage of a battery.

Since we are waiting on the ions switching places, it helps to stir the solution. You cant stir inside a battery too easily, so simply add some MgSO4 (dissolved in water) and slosh the battery around. Every few minutes slosh the battery around again. For a mid sized car battery, I use about 1 teaspoon MgSO4 for each cell (6), dissolved in water, and then fill the rest of the cell up with water.

As for the aspirin, that’s also not a wives tale believe it or not. The aspirin (non buffered) is converted to acetic acid, which both changes the potential of the battery and helps attack the sulfate buildup. This is an emergency last resort though, because your battery will begin to corrode internally when you do this. Magnesium sulfate is much better for a long term solution. Another short term solution that may work is pouring some coca-cola into the cells.

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