12 to 24v

[Nica]

You are correct, pos to neg adds 12 volts with every battery you add. Pos to pos increases amperage instead. There are several places online that show you the theory behind it, the method works both for big batteries and for little bity ones. Here is a link, there are many others if you do a search for "batteries in series".

[url "http://www.zbattery.com/seriesparallel.html"]batteries[/url]

Hope this helps.
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