BigT Posted January 3, 2014 Share Posted January 3, 2014 Hi all, Bit of a dilemma with my new charger and reading through countless other threads hasn't unearthed the answer so here goes... I've only just bought the charger to balance charge my 3 x Lipos. I decided to charge the biggest one first which is a Zippy 4000mah, 2s, 7.4v, 25c. I set up the charger by connecting the mains leads into the charger with deans connectors for the lipo at the other end. I programmed the charger to do a balance charge at 3.0A current and 7.4v(2s). I pressed for 3 secs to complete the battery check and it confirmed that I wanted to charge a 2s lipo. I also had to plug the white 3 pin connector from the lipo into the side of the charger to get it to charge so I'm assuming that this is correct? A point to note is that I selected 3.0a current because I read that I could select up to 4.0a with it being a 4000mah but that it was better to select a lower current for longevity reasons. I then completed the charge which was about 70 mins give or take. I plugged the lipo into a capacity controller to check everything was as it should be and it came up with the following: Lipo - Voltage Total 8.345 Charged total - 96% Difference between 1s and 2s - 0.009 1s - 4.168v 2s - 4.177v Has the lipo been overcharged? The charger was set as above and I thought that I would get a total voltage of 7.4 with each cell being 3.7 max. Can anyone give me some advice please? I'm confused Quote Link to comment Share on other sites More sharing options...
SlideSquad Posted January 3, 2014 Share Posted January 3, 2014 Each cell take 4.2 full charged 1 Quote Link to comment Share on other sites More sharing options...
JasJab Posted January 3, 2014 Share Posted January 3, 2014 Hi all, Bit of a dilemma with my new charger and reading through countless other threads hasn't unearthed the answer so here goes... I've only just bought the charger to balance charge my 3 x Lipos. I decided to charge the biggest one first which is a Zippy 4000mah, 2s, 7.4v, 25c. I set up the charger by connecting the mains leads into the charger with deans connectors for the lipo at the other end. I programmed the charger to do a balance charge at 3.0A current and 7.4v(2s). I pressed for 3 secs to complete the battery check and it confirmed that I wanted to charge a 2s lipo. I also had to plug the white 3 pin connector from the lipo into the side of the charger to get it to charge so I'm assuming that this is correct? A point to note is that I selected 3.0a current because I read that I could select up to 4.0a with it being a 4000mah but that it was better to select a lower current for longevity reasons. I then completed the charge which was about 70 mins give or take. I plugged the lipo into a capacity controller to check everything was as it should be and it came up with the following: Lipo - Voltage Total 8.345 Charged total - 96% Difference between 1s and 2s - 0.009 1s - 4.168v 2s - 4.177v Has the lipo been overcharged? The charger was set as above and I thought that I would get a total voltage of 7.4 with each cell being 3.7 max. Can anyone give me some advice please? I'm confused That is fine a fully charged lipo is 4.2v per cell so 8.4v 1 Quote Link to comment Share on other sites More sharing options...
Bigjimknickers Posted January 3, 2014 Share Posted January 3, 2014 Looks good mine usually end up about 4.19 give or take 0.01 so yea I wrote on my box when I first started, 2s 8.4 v 3s 12.6v & 4s 16.&v as I was totally new to it all & I was getting confused, seems silly now really. 1 Quote Link to comment Share on other sites More sharing options...
jpbp200 Posted January 3, 2014 Share Posted January 3, 2014 (edited) " A point to note is that I selected 3.0a current because I read that I could select up to 4.0a with it being a 4000mah but that it was better to select a lower current for longevity reasons." The best charge rate for a 4000 mAh batt is 1C which = 4Amps. On a 3000mAh 1C = 3 Amps, 2000 mAh 1C = 2Amps and so on. Even though the battery may say it can be charged at up to 2C (4000 mAh would be 8A) or even 3C (12Amps) this is not advisable and there are many many posts about LiPo charge rates so you can make an informed decision yourself. Full charge is 4.2 V per cell (the maximum voltage for a LiPo cell) so 8.4V on a 2S and 12.6V on a 3S. Average charge is 3.7V so 7.4 on a 2S and 11.1 on a 3S which is what you will see on the specs when buying them. Note that they shouldn't be discharged below 3.0V per cell as this will cause irreversible damage or even fire and they should be storage charged when not in use at 3.7v per cell. These parameters can be put into your Overlander. Never store them fully charged for even a small amount of time. Ideally charge them on the day you intend to use them. You should always balance charge them for longevity and the white cable that plugs into the side is the balance charge voltage cable that tells the charger the individual voltage of each cell. Edited January 3, 2014 by jpbp200 1 Quote Link to comment Share on other sites More sharing options...
BigT Posted January 3, 2014 Author Share Posted January 3, 2014 Thanks for all the replies and advice guys, it really is appreciated. Just been reading through your reply jpbp and understand most of it but find myself getting quickly confused! Just to clarify.... Am I charging the 4000mah at 4A current charge from now on? Also, my other two Lipos are 2500mah and 2700mah. Do I charge them at 2.5A and 2.7A? Or do I round up or down? On another note, my LVC is set at 3.2v and my RC car momentarily stops to indicate the LVC coming into play. When I plug the capacity controller into the Lipo would I expect to see the total voltage over BOTH cells at 3.2 to 3.0 v? Sorry for the noob question but I intend to check the lipo at the first point the LVC next kicks in to ensure it is working correctly. Oh and thanks for the info re the three pin connector..... It did make me wonder Quote Link to comment Share on other sites More sharing options...
Bigjimknickers Posted January 4, 2014 Share Posted January 4, 2014 My voltage checkers say "no 1, 3.7v" then it'll flash "no2 3.7v" then 3 rd it'll say total "6.14v" Quote Link to comment Share on other sites More sharing options...
jpbp200 Posted January 4, 2014 Share Posted January 4, 2014 (edited) "Just to clarify.... Am I charging the 4000mah at 4A current charge from now on? Also, my other two Lipos are 2500mah and 2700mah. Do I charge them at 2.5A and 2.7A? Or do I round up or down?" You are correct - 2500 mAh should be charged at 2.5 Amps and 2700mAh at 2.7 Amps no rounding up or down needed if your charger allows the voltages to be set precisely. "On another note, my LVC is set at 3.2v and my RC car momentarily stops to indicate the LVC coming into play. When I plug the capacity controller into the Lipo would I expect to see the total voltage over BOTH cells at 3.2 to 3.0 v? Sorry for the noob question but I intend to check the lipo at the first point the LVC next kicks in to ensure it is working correctly." When under load the voltage read will be less than when not under load ie when your motor is running your ESC will read 3.2V but when you take the load off and plug the battery into a voltage checker (such as your charger) you will likely see voltages of between 3.6V and 3.8V PER cell giving a total voltage on the whole battery of up to around 7.6v for a 2S and 11.4V for a 3S. This is perfectly normal (less is fine too as long as it's not below 3.0) and since the storage charge is 3.7V per cell it has the added advantage that you will have to spend less time with them plugged into the charger while it adjusts the voltage (either up or down) for storing the batteries! It is always best practice therefore to use your batteries until the low voltage warning kicks in on the ESC (but not past this warning) as this will leave the batteries near enough the correct voltage for safe storage and it is far quicker to lose charge running them in the car than having the charger/discharger do it for you. Plus and most importantly it's a load more fun running batteries down in the car which is the whole point!!!! I think your charger and ESC are working fine. I hope that helps. Have fun. JP Edited January 4, 2014 by jpbp200 Quote Link to comment Share on other sites More sharing options...
BigT Posted January 4, 2014 Author Share Posted January 4, 2014 Thanks again, thats makes sense now. The only confusion that now remains is how long my various Lipos will last if I run them down safely. I'll explain.... When I first ran my car out I was given the lipo charged and ready to go. I never read that it should only be run to a safe level and in my excitement at my new toy, I ended up running the 4000mah lipo pretty much dead. I plugged it into the the capacity controller and it would simply read 0v!! I probably got around 25 to 30 minutes of drive time out of that one battery (if my memory serves me well) but it was clearly a noob mistake and at the time I thought that the battery was kaput! This was when I decided to buy a new balance charger to ensure I was doing things correctly from the off and to prevent things going wrong with other Lipos. Anyway, if the fully charged lipo is fine at 8.4v but can only be run down to a maximum total of 6v, this only gives me 2.4v of 'play time' doesn't it? That's why I was asking whether the total voltage for Both cells was 3.0 - 3.2v as I though that I would be using the majority of the Lipos voltage but this doesn't appear the case. I'll go search some lipo threads to see if I can find an explanation. Quote Link to comment Share on other sites More sharing options...
Luke B Posted January 4, 2014 Share Posted January 4, 2014 (edited) Each cell shouldn't be run down below 3.0/3.1v as this will damage them, so yes you can only use 2.4v from the battery in total from 8.4 (2x4.2) to 6.0 (2x3.0). If your battery has a high enough mAh rating it should last plenty long enough, even though you're not using it over a wide range of voltages. Edited January 4, 2014 by Luke B 1 Quote Link to comment Share on other sites More sharing options...
Martz75 Posted July 29, 2014 Share Posted July 29, 2014 Hi,can some help please?i know it may seem a bit daft but can u use any connector on any lipo? For an example cld I change 5.5 bullet connector to 4mm? Quote Link to comment Share on other sites More sharing options...
smeghead28 Posted July 29, 2014 Share Posted July 29, 2014 Hi,can some help please?i know it may seem a bit daft but can u use any connector on any lipo? For an example cld I change 5.5 bullet connector to 4mm? Put whatever you want on it or though for lipo/brushless set ups people tend to avoid the Tamiya type connector. Quote Link to comment Share on other sites More sharing options...
Martz75 Posted July 29, 2014 Share Posted July 29, 2014 Ok cool,thanks for ur help Quote Link to comment Share on other sites More sharing options...
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