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TheGeneral wrote:what if i took two 3.7v batteries at 4700mah, connected them in parallel and then wired them up to the pcb in a series as if it were a regular 3.7 volt pack but with double capacity. would it work?

hailrazer wrote:Lithium Polymer batteries are the newest and currently one of the best choices for batteries in a portable. They are smaller than other batteries, don't develop a "memory" , and last through more charges/discharges than other types of batteries.

But working with Lithium Polymer batteries can be dangerous and precautions must be observed. Be very careful with polarity when hooking up Li-Po's. Also ALWAYS use a protection circuit (PCB) and a Lithium charger that is appropriate for the number of Li-Po's you will be using.

Lithium Polymer batteries come as single 3.7v cells. These cells can be packed together to get 7.4v , 11.1v, 14.8v , etc Li-Po Packs.
When using a 7.4v pack you will want a 7.4v Pcb and a 7.4v charger. Ditto on the rest.

The following diagrams will be based on wiring the 3.7v cells in series to add their voltages together to get the required voltages we need. Batteries wired in series are wired like so :



This is the typical battery most of us use because it has a relatively high capacity for a very small size and cheap price:
http://www.batteryspace.com/highpowerpo ... arate.aspx" onclick="window.open(this.href);return false;


Here is an example on how to wire the different sets of Li-Po packs you might be using :

7.4v pack. (Two 3.7v Li-Po's)


For the Pcb you will need the following :
http://www.batteryspace.com/pcbfor74vli ... limit.aspx" onclick="window.open(this.href);return false;

For the charger you will need the following:
http://www.batteryspace.com/smartcharge ... isted.aspx" onclick="window.open(this.href);return false;

11.1v pack (Three 3.7v Li-Po's) :


For the Pcb you will need the following :
http://www.batteryspace.com/pcbfor111vl ... ocket.aspx" onclick="window.open(this.href);return false;

For the charger you will need the following:
http://www.batteryspace.com/smartcharge ... isted.aspx" onclick="window.open(this.href);return false;

14.8v pack (Four 3.7v Li-Po's) :



For the Pcb you will need the following :
http://www.batteryspace.com/pcbfor148vl ... ocket.aspx" onclick="window.open(this.href);return false;

For the charger you will need the following:
http://www.batteryspace.com/smartcharge ... isted.aspx" onclick="window.open(this.href);return false;

Talakoski wrote: So I will need 2 of these for my project?

Hifeno wrote:Is it possible to wire 3 3.7v 4300mah together to get 11.1v and 12900mah and if so how and what kind of charger and circuit

Also I have them connected right now to output 11.1v 4300mah and when I plugged in the charger to them it only took 30 or 45 min for the indicator light on the charger to say they were charged. Is that normal?