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Can you run loads off the battery at the same time you are charging? Answered

I have a small wind turbine which I use to charge a 5 amphour sla battery.  I plan to charge it using an anyvolt micro set to 13.5 volts.  I don't have a charge controller.  For the present I plan to cut charger power manually.  

If I am pumping 13.5 volts into the battery, then what happens to electronics designed to run on 12 volts if I run them in the circuit.  How do I charge the battery at 13.5v and run 12v devices off it at the same time?


That is how a battery in a car works. The battery stores a charge produced by an alternator while a car is running. The battery helps start the car and energizes all electric and electronic components while you are driving your car.

Thanks for the information. I have since done some testing. When a car is off the power voltage is 12.6 volts. That is normal for a fully charged 12 volt battery. When the car is on, the voltage is 14.72 volts. So anything plugged into the cigarette lighter adapter can sun off both voltages.

Thanks for the information. You mentioned this setup is like a car. I have one more question. It is bad to overcharge a 12 volt battery so how do cars stop from overcharging? The alternator seems to generate a constant 14.72 volts. Does it continue to do this long after the battery is fully charged. Is it okay for car batteries to receive this voltage constantly?

There is a lot of information in the web about how alternators work. You might find the information you seek.

Yes you can. However, if your loads exceed the charger, then the battery will begin to drain to a less and less charged state. As the battery drains down, you will begin to overload the charger. However, if you are loading Less than the charge amperage, then it will not hurt at all. It will only take longer to charge the batteries. I agree with WRIVERA6's answer.

You can't run loads off the _battery_ while it's charging. Depending on how much power the generator is supplying, you may be able to run additional loads off the generator in parallel with the charging battery... or the generator may just keep the battery from running down as quickly.

As to what happens with a 12V device connected to 13.5V... That depends on the device. Things intended to run off a car's 12V supply may not object, since I believe older cars (at least) had exactly that generator-in-parallel-with-battery setup. In general, the safest thing to do is check the manual for that particular product and see what maximum voltage it will tolerate -- or, if you don't have the manual, contact the manufacturer.