All Tools Supply, Inc. Logo All Tools Supply, Inc. Ph : 817-483-0700
204 Twilla Trail Fax : 817-444-4719
Azle, TX 76020.



How long should I charge my battery and at what current?

It is generally recommended to use as low an amp charge as the battery will accept over a longer period of time. A 10-20 amp charger can charge most automotive batteries. Fully charging a completely discharged automotive battery, for example, with a 10-amp charger may take approximately 6-10 hours at a temperature of 80°F. Lower ambient temperatures require a longer charge time.
Some chargers automatically adjust the current and length of charge according to the battery's state of charge and then shut off when the battery is fully charged. If the charger requires manual adjustment for current or shut-off, check the charger's instructions to determine the proper current and length of charge based on your battery's rating.

What will happen if I don't charge my battery properly?

Under-charging - Continually operating a battery in a partial state of charge, or storing the battery in a discharged state will result in sulfation. This process is the formation of lead sulfate crystals on the plates of a lead acid battery. It reduces performance and may cause premature battery failure.

Over charging - Causes accelerated corrosion of the positive plates, excessive water consumption, and in some cases, damaging temperatures within a lead acid battery.

In the case of deep cycle batteries - charge after each discharge and/or after storage of 30 days or more. It is recommended that a deep cycle battery not be discharged below a 50% state of charge. Recharging a severely discharged battery (below 50% state of charge) can result in the battery becoming overheated or overcharged.

What type and size of charger should I buy?

Type: The advantage of an automatic charger is convenience. Once it is connected to the battery, the charger does the rest.

The advantage of a manual charger is cost. It is less expensive and equally effective, but requires a greater level of supervision.

Size: To select the proper size of charger, you must consider the battery's capacity and the amount of time that will pass between charges. Larger batteries require higher ampere ratings.

Why won't my battery take or hold a charge?

The following are possible reasons:
  • The battery may have a bad cell or an internal short circuit and therefore be irreparable.
  • The battery may be so severely discharged that it may not be possible to recharge it or require a professional caliber charger to charge it.
  • The battery was not given adequate amount of time to accept charge.
How can I test my charger to see if it is bad?

Check the ammeter gauge (where applicable) or the indicator lamp on the charger. If working properly, the ammeter gauge should deflect to an amperage level above zero once the charger is connected to the battery and turned on. If you suspect your battery is in working condition and it does not recharge within a few hours, your charger may not be working correctly.

How do I know when to replace my battery?

You might need to replace your battery if:
  • Your starter motor is experiencing slow or interrupted turnover.
  • Your instrument panel battery light indicates battery discharge for extended periods after the engine is running.
  • Your battery seems to lose power quickly in cold or extended starts.
  • Your headlights dim at idle.
Please note that any of these warning signals may also indicate a problem with the electrical system in your vehicle and not necessarily a battery failure. A battery that is about to fail will often give little or no warning. If you suspect that your battery is failing, test it yourself or have it tested by a professional as soon as possible.

How do I replace my battery?

1.   Visually inspect the battery connections and note the location of the positive (+) and negative (-) posts. Identify which of the posts is grounded (connected) to the chassis.
2.   In the case of a negative-grounded battery, disconnect the negative (-) cable from the battery with a battery cable puller. Then disconnect the positive (+) cable.
3.   In the case of a positive-grounded battery, disconnect the positive (+) cable from the battery with a battery cable puller. Then disconnect the negative (-) cable.
4.   Remove the hold-down clamp which holds the battery in place.
5.   Lift out the battery.
6.   Inspect the battery tray for corrosion or damage. Neutralize and clean or replace the tray and attaching parts as needed.
7.   Inspect the battery cables for damage. Clean or replace the cables as needed to ensure a good connection.
8.   Install your new battery and secure it with the hold-down. Be sure the new battery is the same voltage and group size as your original equipment battery. Check to ensure that it has at least the same cold-cranking amp (CCA) and reserve capacity (RC) ratings as specified by the original equipment manufacturer.
9.   In the case of a negative-grounded battery, attach the positive (+) cable to the positive (+) terminal Then attach the negative (-) cable to the negative (-) terminal.
10.    In the case of a positive-grounded battery, attach the negative (-) cable to the negative (-) terminal. Then attach the positive (+) cable to the positive (+) terminal.
11.    Make sure not to over-tighten.

My battery light comes on when I'm driving, and the voltage jumps back and forth from high to low.

This would typically indicate a charging system or cable connection problem. Take your vehicle to a mechanic to have the charging system, cables, connections and battery tested. This will help determine what type of problem you are having.

My battery keeps failing even though I seldom drive the car.

Batteries will self-discharge while sitting unused. Also, every vehicle made since the late 1970’s will have some key-off electrical drain, from the computer memories, which may discharge the battery below a no-start condition within a few days to two weeks. Connect a small charger to the battery occasionally. If this problem continues to occur, have the vehicle tested by a mechanic for excessive key-off electrical drain.

My battery quickly gets corrosion build-up on the terminals.

 Although all batteries contain highly corrosive sulfuric acid, corrosion should not occur under normal conditions without spillage or one of the following:

Overfilling: If too much water has been added to the electrolyte, it may have overflowed to the battery, which will corrode the terminals. Only add water up to the battery manufacturer’s reference point (e.g. bottom of the split ring) if the electrolyte is at or below the plates.

Overcharging/overheating: Overcharging by the alternator or normal charging at an extreme battery temperature can result in excessive gassing of the battery, which may produce increased corrosion.

Metallic exposure: When an electrical wire is exposed to salt particles in the air, corrosion will eventually occur. Remember to keep connections clean, tight and sealed by a corrosion inhibitor. Do not overfill the battery or allow it to become overcharged or overheated. If battery corrosion persists, check with your local electrical professional.

My battery starts the car sometimes but not at others times.

This is probably not a battery problem. If the problem occurs only after the vehicle sits overnight or for a day or more before starting, the problem is often a low state of charge. If the battery starts the vehicle once the vehicle has been started recently, test your battery to determine its state of charge. Also, make sure that the alternator is adequately charging and that all the connections are good. If problem continues, see your mechanic.

What is the proper way to store my battery while not in use?

Keep your battery in a cool place away from the reach of children and pets. Avoid extreme cold or hot temperatures, as they can produce damage to a battery. If storage time exceeds two months, it may be necessary to fully recharge the battery before re-installing it.

What is the proper way to dispose of my lead-acid battery?

Most retailers, auto parts stores or service outlets that sell new lead-acid batteries will accept a small number of spent lead-acid batteries for recycling. A call to your local solid waste management center will give you specific information on recycling centers and procedures for your county and state. Because lead-acid batteries are considered to be hazardous waste, it is illegal in most states to mix them with solid waste, or dispose of them in solid waste landfills and incinerators.

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