Polyquest PCM Guard
 

I think I made a mistake by buying these PCM guard for my 5S PQ 20C 3700 LiPo. I bought 2 of them, one is for 2S and another one is for 3S. I just realize that these units cant be used with pulse charger like AstroFlight 109 (which is a very good charger from what Ive heard). Im still new in this Lipo technology. Should I go ahead and by the AstroFlight charger and "throw" these units away, or just buy the a CC orCv charger like Apache? Is it better to use pulse charger or CC/Cv charger? I dont really care about charging time. I hope these LiPo can last as long as possible.. So please shed some light..

If you ever plan on using balancers in the future (which is a good idea), then get a standard CC/CV charger. I use the ICE, and did use the Apache until I short-circuited the output leads.

I think the CC/CV chargers are better for longer life of the LiPos.... I use the AstroFLight 109, but I just bash around.. I don't care how long the lipos last... (the more I care, the shorter it'll last, IMO)... for me.. Maybe once a month, I'll Charge at a very very very slow charge rate... like 50 - 100 mah/hour... In my mind, I think it helps the cell voltage closer by doin' this.. I think there's a damaged lipo pack in my head....

I have the Astro 109 -- what's the difference of a CC/CV charger? Are they capable of doing as many cells? Cell count may not matter to me, i don't knw if I would ever go over 4, let alone 2, but how about amps for larger packs? I'm thinking of getting some 8000mah TP packs.

The Astroflight 109 is somewhat of a pulse charger. It "pulses" the battery to some degree (has been measured up to 4.35v for very brief periods). Otherwise, it is mostly a CC/CV charger. But because of this pulsing, it would be better classified as a pulse.

CC/CV and pulse charging are just different techniques. Cell count and amp rate depends on the charger. The Astroflight 109 can charge at up to 8amps, so it could charge a 8000mah pack at 1C. The Duratrax ICE charger (one I use) can charge at up to 8 amps also.

So metalman, are you suggesting that using CC/Cv with the PCM is better than pulse charger for LiPo? As I said earlier, Im concern about the life of the LiPo. Cant afford to buy $200-300 batts anymore..

And one more question about balancer, what type of balancer are you using? Can you suggest the best one for Polyquest LiPo?

Im also going to buy LVC but not sure which one is good. I was looking at the Kokam's (http://www2.towerhobbies.com/cgi-bin...?&I=LXJDJ0&P=7) and this (http://rcworldofplanes.net/prodView.asp?idproduct=49). Which one should I get? Is there any other accesories that I have to buy before I can use this LiPo system?

Sorry for all these questions but I really need some advice..

mothman, the fma lvc your talking about works great and needs nothing special to install. its only rated for 4s lipo, who knows if it will work with anything bigger? i have only used it with 3s. the other device should work the same and it can handle more cells.
cell balancing can be done very effectively by just checking each cell through the taps with a multimeter. i always check mine before, during, and after a charge. it only takes a few seconds and i have yet to have any problems with my batteries going bad. if you do find a cell thats out of balance with the rest, charging it individually is easy using some small male pins wired on the end of a deans plug. a cell balancer is foolproof and may save you some time. my intentions were to buy a balancer at first, but the plug i made works safely and effectively and cost about nothing.
:D

whats the best CHEAP lipo set up i could run with my e-revo? i plan on running a 7xl and at least 5s lipo. maybe 6 if the 7xl and warrior can handle it. also, im looking for at LEAST 6000mah and would like to be able to balance them and somewhat of fast charge them. like an hour or hour and a half?

I think all li po's can be charged in an hour or a littlebit more....
but for price.... I'm not sure... Lipo's are expensive, except for the cheaper lower discharge ones.... like 6C

Thanks fearanloathing. just realized about the the KOkam's LVC is only for 4S. Seems like I have no option other than this one (http://rcworldofplanes.net/prodView.asp?idproduct=49). Has anybody try using this LVC? How does it performs? Or is there any other better LVC??

I dont really know about balancing. But I think the PCM unit that I bought can acts as a balancer while charging. Not sure though can someone confirm this?

Balancers won't work well with the 109, as they limit the voltage to 4.20v (+/- .05v, depending onthe balancer). The PCM guard isn't actually a balancer at all, it just cuts the charge if a cell gets to 4.35v (which is too high).

I personally don't use a balancer (yet). I monitor my LiPos with a volt meter on the taps, and if a cell gets higher than the rest, then I will charge each cell individually. If I do get a balancer, it will be one that I make. This one would limit the max voltage to a user-settable voltage, and if the imbalance in a pack is too great, then it will cut the charge. The Thunder Power balancers (with the appropriate connector) would work well with Polyquest packs.

As far as LVC devices go, you have a lot of choices. I would never get anything that cuts off any lower than 3v per cell, and the FMA one cuts at 2.6-2.7v. The Li-Saver would work, but I have heard of a recent issue with it causing glitching. Right now, I am making LVC devices for 2s-4s Lipo (and possible 5s), that will cut at about 2.95v/cell, but will pulse the motor at about 3.05v/cell. The pulsing is noticable, as the car will sort of stutter. This means that the battery is done, it's time to take it in. If you are interested, let me know. I am asking $15 shipped to the U.S.

Go for the 5s Lipo. It won't disappoint you. With 5s 6000mah, you are going to spend quite a bit. Just to give you an idea, it will cost $300-350 depending on the brand and quality).

Modern Lipos can be charged at 1C, which means one hour to do about 90% of a charge, and then another 15-30mins to do a 100% charge. Some cells, like the Kokam 3200s can be charged at up to 3C, so that means 20mins for 90%, and maybe ~45mins for 100%.

To balance them, you could by the Thunder Power balancer, and just stick the proper plug(s) on depending upon the brand of the battery.

i have actually found 6000mah 2s packs for $125. not to mention thats at 15C with is 95 continuous amps.

Squee..?.. really... Where.. Hook me up...

You can get a Maxamps 2s4p of 1500mah cells for under $120... That's 2s and 6000mah.