Specifications

topped up if they haven’t been used for a few days, as lipos do not self discharge half as quickly
due to lower internal resistance and superior chemistry.
What about series vs parallel?
Lipos wired in series (+ to – ) will increase the total voltage. For example, two 2s lipos wired in
series will create a 4s lipo. The mah capacity will remain the same.
Lipos wired in parallel (+ to +, - to -) will increase the total mah available, For example, two 2s
5000mah lipos in parallel will create a 2s 10,000mah lipo. The voltage remains the same.
The 's' after 2s for example means Series, and is how many cells are wired in series within that
pack (it does not stand for cells). The 'p' after 2s2p for example is how many cells are wired in
parallel within that pack (if any). A 2s2p pack has four cells in total, with 2 pairs of cells wired in
series to create a pair of 2s lipos, then they are wired in parallel to double the mah capacity. This
is why some lipo packs in the 6000-8000mah range are often 2s2p or 4s2p packs which are
rather large in size.
When using batteries in series, the voltage can vary, but the mah capacity and c rating must be
the same on both lipos (the age and condition too ideally). When using them in parallel, the the
voltage, capacity and c rating must all be equal to prevent damage to the lower spec lipo thorugh
over discharge.
Waterproofing?
Using some silicon sealant on the open ends of lipo packs that are covered in shrink wrap can
help (you can sometimes buy them this way), but the main area for concern are the connectors
that are not so easily waterproofed. Rusty balance taps will give inaccurate readings and cause
issues when it comes to charging and balancing your packs. Best to avoid running lipos in or near
water unless you have the initiative or imagination to come up with a solution to this problem.
Puffing?
This is a symptom displayed by lipos that have been over discharged. They will swell up and
often become squishy to the touch, but sometimes also ‘deflate’ once cooled down. The easy way
to avoid this is to choose properly spec’d lipos for your application, or to tone down your setup so
that the lipos have some headroom in terms of what you are asking of them. Lipos that have only
slightly puffed can still be used, bearing in mind the above piece of advice, but lipos that look like
balloons afterwards are best either disposed of safely, or returned to the retailer for warrantee
purposes. Safe disposal is generally considered as immersing the packs into a salty water bath to
discharge them down to 0v, thus removing all their energy and potential to cause damage if
punctured.