extra battery

[Guest]

i currently have2 batterys on my boat which are switched so one cannot run down ie dedicated to the engine
i want to add a further battery is it as simple as addidng the connectors from the existing battery across & will it then discharge & charge via the existing connectors or is it not as simple as that any advice would be greatly appreciated
i tried to post this on the practical forum but after 5 minutes it dissapearedthanks in advance alan

 

[Guest]

Yes. Connect the batteries in parallel (red to red and black to black). This will turn your two batteries into one large one with double the capacity (amps) but still keep the system 12 volts. You must make sure that the batteries are of the same type (e.g amp rating). You should also make sure that they're in similar condition otherwise the poorer of the two will drag down the performance of the other one to the same level.

Paul

 

[Guest]

Better still place blocking diodes on the auxiliary batteries and a two way boating isolating switch. This will allow both auxilliary batteries to be selected seperately or together and to be charged while not discharging into each other.

 

[Guest]

But the diode drops the voltage

so the auxiliary batteries don't get a full charge. If you want to make the auxiliary bank charging process automatic, the simplest and best way is with a battery combiner, or equivalent. You can review information and download owner's manuals with circuit diagrams from http://www.yandina.com/combInfo.htm