Alan Moore Posted October 16, 2011 Share Posted October 16, 2011 Hi I have a GensAce 2200mah 3 cell li-po. When I finish flying the cell voltages are all about the same at 2.8v, however when I charge it, fully charged the voltages are 4.15, 4.15 and 4.20. I am using a good balance chareger, using a rate of 1.4a. Does anyone know why the fully charged voltages are not consistent please? Alan Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted October 16, 2011 Share Posted October 16, 2011 hello alan... i cant expain why you have different readings with each cell---- could be your bal charger or a lot of other things as well-this has been discussed in the past and the conclusion was that it didn't make a lot of difference to everyday use of the lipo ..... and was nothing to get concerned about.... ken anderson ne....1 .. lipo dept. Quote Link to comment Share on other sites More sharing options...
Ben B Posted October 16, 2011 Share Posted October 16, 2011 If those readings are true then those cells aren't balanced.. What are you measuring the cell voltages with? It could be the device you are using to charge it or the one to read the cell voltages.... Then again they're not massively out so unless you're planning on running the pack down to the last few mA (bad idea anyway) then it won't really matter. Quote Link to comment Share on other sites More sharing options...
PatMc Posted October 16, 2011 Share Posted October 16, 2011 A 1.2% difference in voltage is nothing to be concerned over. It's probably well within the charger/balancer's tolerance range. If the charger is programmed to cease charging when one cell reaches 4.2v & the other('s) are within a certain percentage then this would account for the small difference. It means that the charge is completed faster at the expense of a minute amount of capacity. If the cells were wildly different & then charged without any balancing there's a risk of one or more cells being overcharged which could be dangerous.BTW if you are quoting the voltages as shown on the charger via the balance mode display this is not always reliable. These are measured separately within the charger there are sometimes discrepancies in their calibration. (Same applies to the little plug in cell voltage checking gizmos) Best to compare the voltages of each cell individually using a DVM then check this against the charger's display. Edited By PatMc on 16/10/2011 15:33:59 Quote Link to comment Share on other sites More sharing options...
Alan Moore Posted October 16, 2011 Author Share Posted October 16, 2011 Thanks to eveyone who has contributed, I think I am worrying about nothing! I will take my chargers read-out with pinch of salt. Alan Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted October 16, 2011 Share Posted October 16, 2011 Encountered something similar at the club this weekend. A clubmate just wasn't getting the performance from a 3s1p 2200mah 25C pack. Also, when he [put the pack on to cage it was coming up with various low voltage warnings. Put the pack on my battery doctor and the three cells read 4.44v 4.42v and 3.79v respectively. The pack voltage being 12.65v. It looks as though charging without the balancer in circuit had returned a fully charge pack, but the distribution of that charge was horribly out, with two cells being dangerously over voltage. We attempted a balance, and the hig voltage cells came own to a safe level of 4.1v but the third cells was not co-operating. He's tried charging that single cell to get the three within a reasonable range, but the pack will want a couple of balance charges, in a lipo sack, to see if it can cut the mustard. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.