#Car battery charger amps series#

We were always properly dressed for motorcycle riding and almost always wore our helmets. It was an inconvenience to re-install the batteries, but if weather permitting wife and I decided to 'suit up' and go for a ride, that is what we did. You need to make sure that the charger voltage remains low enough to prevent overcharging if the battery remains connected for months at a time.ĭuring the winter in Dayton, OH, I would remove our motorcycle batteries and bring them into our heated basement for storage and as-needed charging.

#Car battery charger amps series#

Being unregulated their low load voltage would float up above the needed battery float voltage, including enough voltage margin for an LM317 regulator in series at the low float current rate you'd need for that size battery.Ĭlick to expand.Yes, a properly sized lamp will do the job, but the voltage drop across the lamp will decrease as the battery voltage approaches the charger voltage and the lamp resistance will therefore also decrease. Then again there are trickle or float chargers purpose made for this, and surely some DIY circuits floating around the 'net that need nothing more than an unregulated little 12VDC wall wart as a power source. You might want to experiment with different resistances or use a linear regulator set to a target float voltage (using an LDO regulator if the voltage margin isn't enough otherwise which it may not be if the charger is regulated, or even a diode in series if the voltage margin is smaller still). Even an AGM battery can have outgassing if the electrolyte is being liberated.Īs Bluejets mentioned there are different types of 'standard battery charger' now and some have their own regulation. Even that, maybe too high for long term storage. If it's more than a couple dozen mA it is too high. I'd measure resultant current when that is put in place with the battery fully charged already. Obviously a multimeter set on hi current range to initially monitor the rate.įinally there are some pretty cheap plug pack trickle chargers on Ebay etc. If too much drop, perhaps a headlamp which normally comes as 55w/75w hi and lo beam.Ĭonnect the bulb in series between the charger and the battery.įailing that some nichrome wire mounted on a air cooling frame with one end fixed to the charger output and the battery under charge via a slider crocodile clip.

You could, for example, start with say a brake/tail incandescent lamp which I think is 21w on the brake section. If thinking along the lines of a resistor, the cheapest most effective would be to experiment with a range of 12v auto bulbs until you get the desired effect. Problem could come from just what type of charger you have if considering any active electronic component as some of these simple battery chargers are really just pulsed dc with some degree of ac component. the smaller the voltage difference between the charger and the battery, the smaller the charge rate. Charge current should be able to be reduced using some means of voltage control.