Hi I need a charger that can recharge dead car batteries, motorcycle batteries, lawn mower batteries and what ever other kind I have I also would like it to be able to keep batteries charge over the winter kind of like a battery tender. I am hopping that sears will have something like this so if you could please post the kind that I should get. what amps and volts do the different batteries require for charging and for keeping them charged over the winter?

 

Typically, no one battery charger can meet every need to charge all types of batteries under all conditions without plunking a wad of bills out for high quality, muti-setting, heavy duty charger. HOWEVER, that being said...

Selction of a charger to meet your needs should be based on the following:
The smallest battery you want to charge.
The largest battery you want to charge.
How long you want to wait while charging.
Whether your charger can start the car .
How much you want to spend.

Small batteries like motorcycle and lawn and garden tractors are generally charged at no more than 2 amps. So the charger should have a 2 amp setting. For monthly maintenance charging of car batteries, a 6 or 10 amp setting will charge safely without causing problems.

A discharged battery can take a long time to charge at 10 amps. A charger that puts out 20 to 30 amps would be a good choice and prevent battery damage from overheating and internal grid damage.

A good selection would be a charger with a 2,6,10 amp setting, or a 2, 10, 20 amp setting.

Unless you are in an agricultural or industrial setting where 6 volt batteries are still used, almost all other batteries you encounter will be 12 volts. A 12 volt charger will suffice. If you feel the need, 6/12v chargers are available, but more costly.

A 40 amp or above quick charger can "Potentially" and permanently kill a battery if not carefully used and monitored. Here's why.

The amount of charging current a battery will take is dependent only on 1 thing (assuming an infinite current source) and that is the difference in voltage between the source (charger) and the battery. Charging current can be limited by the current limiting circuit or regulator in the charger (if so equipped). The switch setting, 2, 10, 40, 200 amps, etc., sets the output voltage up or down and therefore limits the voltage difference between the charger and battery and hence, the charging current.

How fast a battery can safely be charged depends on reaching the max safe internal temperature the battery can handle, typically around 130 degrees, and the gassing that takes place when charging. Light gassing noted by small bubbles thru the vent holes is good. Violent bubbling at high charging rates can knock the active material out of the grids. This lead and lead dioxide material may eventually settle out and cause internal shorts. Cracking of the plates can also occur due to volume change.

Now, I'm not saying that a quick charger prudently used, or a boost start charger will destroy every battery. Be aware that the voltgage output on the highest settings can reach 18 volts or more and that is hard on all the electronics in the vehicle. Use these setting only as long as necessary to get the car started.

Since batteries will self discharge over time, perform a maintenance charge once a month. A battery can completely discharge with 3 months of inactivity and the plates undergo a chemical process called sulfation. This may shorten the life of the battery or terminate it completely. Check the water level before your maintenence charge, or every 3-6 months. The best time to water your battery is before charging to mix the water and acid. Keep the battery clean. A fully charged battery will seldom freeze even in sub-zero weather. A partially discharged battery can freeze anywhere below 32 degrees.

A lot of summarized information to answer you question, but I feel it will help with your battery maintenance.

 

So if I wanted to make sure that my car battery that is not used all winter stayed charged what setting and how would i go about doing this if I i had a automatic charger? what about my motorcycle and lawn mower battery?

 

An automatic charger simplifies the process. Most automatic chargers have a cutoff circuit and a current limit circuit built in.

On the car batteries, assuming you use a 10 amp setting, take the vent caps off, and check the level. Hook up your charger and turn it on. Note the charging current. Should be 10 or less. Let the battery charge until the current drops to about 1-2 amps. This is about where most automatic chargers will cutoff. Some will cycle on and off like a trickle charger, but I wouldn't recommend leaving it on much longer than it takes to hit the cutoff point of the charger. I've found that most batteries are close to being fully charged at this point (verified by measuring the specific gravity with a hydrometer).

Small batteries pose a greater challenge. They typically only have a one year warranty, thus only an expected one year life expectancy, but I have had a motorcycle battery last for years with proper care. Problem here is the charger. If you have a 2 amp charger with an automatic cutoff, use it as stated above. The first time used on a small battery, monitor the battery closely for signs of overcharging. These would be violent bubbling and the battery case getting real hot. The case should only get warm to the touch. If you use a wall type charger, hook it up, turn it on. Generally a small battery should not need more than one to two hours to top off.

An accurate voltmeter can also help determine battey condition. Typically, depending on battery age, about an hour after charge the battery voltage should stabilize above 12.5 volts and stay there for weeks. When it reaches 12 volts, charge it again.

 

So if I have a battery that is sitting for 8 months a year I should charge in for a certain amout of time every month? Thanks for the info it has been great so far.

 

Yeah, just keep it charged. I've let one of the cars sit for sit for 6 months, but kept the battery charged. As an experiment, when I left the IROC on jackstands for 3 months, I left the battery uncharged (planned to replace it before winter, anyway). It was at 9 volts when it was recharged. Although it came back up, it had lost capacity during the 3 month downtime and would not hold the charge. Within a couple weeks, it would not start the car.

 

I have an automatic 10 amp charger that can charge 6 and 12 volt batteries. It wasn't expensive, and it does everything I need it to. If my battery is completely whomped, sometimes it takes 3 or 4 hours to charge it enough to start the car, although in those cases I just leave it on overnight.

I don't really care for the high current chargers. I think a slower charge puts less stress on the battery. If I need a quick start on a dead battery, I grab a battery pack. Those are a must-have anyway.

 

I just use a 2/10/40 or 50 not sure from walmart. It has always worked great for me. It's automatic so it will maintain a battery--start/stop charging as needed. It was cheap and works on my mower (69 cub cadet), my Camaro, wifes Cutlass, the Tahoe. On my Camaro when it sits in the winter I check it monthly and run the 2amp charger as needed.