lipo help
01-19-2010, 06:30 PM
#2
The 1st number is the number of cells wired together in series and in series, voltages adds and capacity (mah) stays the same - so 2S is 2 3.7v cells wired together for a total of 7.4v 'nominal'.
Lipo is confusing cause there are 3 voltages tossed around and 2 are used interchangeabley. The 3.7volts for an individual lipo cell is referrred to as the nominal voltage. When a lipo cell is charged, it charges to a max voltage of 4.2v. So that same 2S thats called 7.4v is really 8.4v (4.2v/cell x 2 cells) when charged. Nominal voltage is basically for comparing. There is also a minimum voltage (~3v/cell), thats the 3rd voltage used in talking about lipos.
Now the 2nd number is number of cells wired together in parallel (in parallel, voltage stays same but capacity adds). So a 2S2P is actually a total of 4 cells - two cells are wired in parellel and then these 2 pairs are wired in series. If we use 5000mah cells for example - 2S1P is a 8.4v 5000mah lipo battery. But a 2S2P is a 8.4v 10,000mah (2 x 5000) lipo battery.
We are getting lazy - with no cells wired in parallel, we'v dropped the "1P" since its pretty meaningless anyway. As you can see, parallel is usually done to add capacity and increase run time.
Lipo is confusing cause there are 3 voltages tossed around and 2 are used interchangeabley. The 3.7volts for an individual lipo cell is referrred to as the nominal voltage. When a lipo cell is charged, it charges to a max voltage of 4.2v. So that same 2S thats called 7.4v is really 8.4v (4.2v/cell x 2 cells) when charged. Nominal voltage is basically for comparing. There is also a minimum voltage (~3v/cell), thats the 3rd voltage used in talking about lipos.
Now the 2nd number is number of cells wired together in parallel (in parallel, voltage stays same but capacity adds). So a 2S2P is actually a total of 4 cells - two cells are wired in parellel and then these 2 pairs are wired in series. If we use 5000mah cells for example - 2S1P is a 8.4v 5000mah lipo battery. But a 2S2P is a 8.4v 10,000mah (2 x 5000) lipo battery.
We are getting lazy - with no cells wired in parallel, we'v dropped the "1P" since its pretty meaningless anyway. As you can see, parallel is usually done to add capacity and increase run time.
01-20-2010, 06:44 AM
#3
The 1st number is the number of cells wired together in series and in series, voltages adds and capacity (mah) stays the same - so 2S is 2 3.7v cells wired together for a total of 7.4v 'nominal'.
Lipo is confusing cause there are 3 voltages tossed around and 2 are used interchangeabley. The 3.7volts for an individual lipo cell is referrred to as the nominal voltage. When a lipo cell is charged, it charges to a max voltage of 4.2v. So that same 2S thats called 7.4v is really 8.4v (4.2v/cell x 2 cells) when charged. Nominal voltage is basically for comparing. There is also a minimum voltage (~3v/cell), thats the 3rd voltage used in talking about lipos.
Now the 2nd number is number of cells wired together in parallel (in parallel, voltage stays same but capacity adds). So a 2S2P is actually a total of 4 cells - two cells are wired in parellel and then these 2 pairs are wired in series. If we use 5000mah cells for example - 2S1P is a 8.4v 5000mah lipo battery. But a 2S2P is a 8.4v 10,000mah (2 x 5000) lipo battery.
We are getting lazy - with no cells wired in parallel, we'v dropped the "1P" since its pretty meaningless anyway. As you can see, parallel is usually done to add capacity and increase run time.
Lipo is confusing cause there are 3 voltages tossed around and 2 are used interchangeabley. The 3.7volts for an individual lipo cell is referrred to as the nominal voltage. When a lipo cell is charged, it charges to a max voltage of 4.2v. So that same 2S thats called 7.4v is really 8.4v (4.2v/cell x 2 cells) when charged. Nominal voltage is basically for comparing. There is also a minimum voltage (~3v/cell), thats the 3rd voltage used in talking about lipos.
Now the 2nd number is number of cells wired together in parallel (in parallel, voltage stays same but capacity adds). So a 2S2P is actually a total of 4 cells - two cells are wired in parellel and then these 2 pairs are wired in series. If we use 5000mah cells for example - 2S1P is a 8.4v 5000mah lipo battery. But a 2S2P is a 8.4v 10,000mah (2 x 5000) lipo battery.
We are getting lazy - with no cells wired in parallel, we'v dropped the "1P" since its pretty meaningless anyway. As you can see, parallel is usually done to add capacity and increase run time.
01-20-2010, 09:40 AM
#4
The only way I can explain this is to say to balance what is provided on the lipo thru the balance plug.
If you have a 2S2P, it will have a 2 cell balance plug and when you plug that into a charger, it will show as 2 cell - so you're balancing the 2 pairs of cells against each other. If there were 4 cells involved, your charger would think it was a 4S and wouldn't charge it -voltage would be too low for charger.
If you have a 2S2P, it will have a 2 cell balance plug and when you plug that into a charger, it will show as 2 cell - so you're balancing the 2 pairs of cells against each other. If there were 4 cells involved, your charger would think it was a 4S and wouldn't charge it -voltage would be too low for charger.
01-25-2010, 01:53 AM
#5
if you'd know some electrical terms the first letter "S" would mean Series and the 2nd Letter "P" would mean Parallel. they just made it shorter for it to be more simpler to write down I guess... so 2S2P => 2 Series 2 Parallel
hope i made things easier to remember
hope i made things easier to remember
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
