====== parallel-serial ======
{{ http://www.12voltbattery.info/images/content/batteryWireDiagram.jpg?150}}

Electrical components like [[electrical:12v:deep_cycle_battery|batteries]] and [[electrical:solar:panels|solar panels]] can be used independently or combined.  If combined, they are connected //in series// or //in parallel//.((more complicated arrangements are possible;  see below))  For the following examples we will consider //two items// -- batteries, solar panels, etc. 

**Series** connections **double the voltage** while the current (or capacity in Ah when dealing with batteries) remains unchanged. 
  * common example:  2 6v, [[electrical:12v:battery_capacity|200Ah]] [[electrical:12v:deep_cycle_battery#v_golf_cart_batteries|golf cart batteries]] in series = a 12v, 200Ah battery //bank//.((a bank acts as a single unit, not as two separate batteries)).  This is a recommended configuration.
  * less common example:  2 12v, 90Ah batteries in series = a 24v, 90Ah battery bank.

**Parallel** connections **double the current** while the voltage remains unchanged. 
  * common example:  2 12v, 90Ah batteries in parallel = a 12v, 180Ah battery bank.   This is not a recommended configuration.  It is not due to any shortcoming of parallel connections;  [[electrical:12v:deep_cycle_battery#chain_store_batteries|12v "deep cycle" or marine batteries]] are rarely real deep cycle batteries and suffer from the treatment van life dishes out. 

[[https://caravanchronicles.com/guides/how-to-connect-two-batteries-in-parallel/|{{https://caravanchronicles.files.wordpress.com/2013/02/connecting-two-batteries-in-parallel.jpg?400}}]]

Wide parallel configurations (like 4P) are difficult to [[https://www.impactbattery.com/blog/post/how-to-charge-marine-and-rv-batteries-in-parallel|charge/discharge evenly]] without exotic cable configurations. 


===== notation =====

When discussing multi-battery banks it is common to describe the electrical layout with a particular notation.  

**p** = parallel \\ 
**s** = series

Examples:
  * **1p1s** - a single battery
  * **1p2s** - two batteries in series, as one finds in the common 2x6v GC battery setup
  * **2p1s** - two batteries in parallel
  * **2p2s** - two sets of batteries in parallel linked in series as one finds in higher-capacity GC-based setups