12v 50ah vs 100ah

[MottMcFly]

Please pardon me if this has been addressed before. I've run a few searches but could not come up with a thread that answered this.

What are the benefits of running 100ah batteries over running 50ah batteries? Is it as simple as getting twice the running time of devices connected to them?

It seems to me that running a system with 50ah batteries would be more cost efficient in regards to maintenance and replacement.

Thanks in advance to any advice.

Mott

[Sunking]

What are the benefits of running 100ah batteries over running 50ah batteries? Is it as simple as getting twice the running time of devices connected to them?

Yes it means twice the capacity. The size of the battery is determined by how many watt hours or amp hours you intend to use in a day before being fully recharged. To get maximum battery life and the most bang for your buck you only design to discharge only 20% of the capacity. So if you use 20 amp hours, you want a 100 amp hour battery.

[MottMcFly]

Yes it means twice the capacity. The size of the battery is determined by how many watt hours or amp hours you intend to use in a day before being fully recharged. To get maximum battery life and the most bang for your buck you only design to discharge only 20% of the capacity. So if you use 20 amp hours, you want a 100 amp hour battery.

Got it. Thank you

[inetdog]

Just be careful to keep in mind that what counts for running loads is the capacity in watt hours. For a single battery that is AH times V.
When you put two identical batteries in series you get the same AH and twice the V.
When you put them in parallel you get the same V and twice the AH.
Either way, you store twice the energy.

So a 6V 200AH battery will be about the same size and weight as a 12V 100AH battery.