mzs6

iTrader: (15)

Hello, I'm trying to get back into racing 2wd buggies again. Ive bought Zeee’s Premium 2s shorty packs off of ebay and find out these batteries are not very premium since both batteries are more 1500mah short of 6000mah claimed after discharging at 1.5a and charging at 5a. Bought another set off of amazon CNHL shorty with claimed mah of 4900. Those were off 400 - 900mah after doing discharge/charge cycle. I have not used all these batteries at all, yet. So yesterday I bought Proteks 2s 4600 mah at my lhs did the cycle and these set are also not hitting the claimed capacity. These ones are off by 200 - 300mah. So my question is. Am I expecting too much? Or is this the norm?

Thanks

BigBuckORamma

Are you buying HV packs?
And what is the maximum cell voltage you are charging to?
Also, what type of charger are you using?

Also, if your location info is accurate, feel free to head down the road and check out the guys at Tacoma RC Raceway. Scotty and the gang over there are super helpful in the hobby shop with any questions you might have.

the rc guy

you will never get 6000mah outa your packs you clearly dont understand how a lipo works..

Rocket777

And you are so nice and helpful as always. This place is for help not bullying and shaming.

Davv

iTrader: (2)

Hey bud. First I would check your charger settings. Depending on what you are using it will let you set the batteries capacity and it won’t shut off till it hits those number regardless of what the battery says.
Second….battery wise again depending on what you are using them for ie racing or bashing the lower quality ones are great for just banging around and even club racing. But if your serious racing imo trinity batteries are the best. Not to be cliche but I know one of their good racers. He tells me straight they per company will spend miss per battery to get the quality ones even though there are only three factories that make them.
I hope this helps bud. No bullying a-hole ness here

Vertebreaker

iTrader: (6)

I have 2 of those ZEE's Premiums that I've used for 2WD 17.5 blinky and 13.5 wheeler racing and I've had no problem with them and they have seemed to work well. I've been using them on carpet and turf and normally for 5 minute races with a few pre race laps they come off after the race at normally around 7.8 to 8.1 volts. 1 out those 2 batteries does seem to have more punch to it than the other so I'm guessing the discharge rate of the one packs cells are a little more "premium" than the other. I also race with the 4000mah Gens Ace Redlines and never had a problem with 5 or 7 minute races. I'm not sure about others experience racing mod classes or with bigger vehicles. Also as others have mentioned to check your charger settings and make sure it can even charge HV packs up more than a normal lipo.

mzs6

iTrader: (15)

Thanks for the replies. Im using spektrum g2. I guess I was just expecting the labels to actually match.

the rc guy

the labels match the mah. the thing is one will never be able to run a lipo to get every stated mah out . reason we run them to lvc cutoff leaving that amount of mah in a pack ...

BigBuckORamma

But...they...do...match.

You also didnt answer the most important questions i asked above.

Are these High Voltage Packs?
And what is the voltage you are charging them to?

Here is why those questions are important.

The total mAH of a pack is best effort at full capacity. Sometimes its a little more, sometimes it is a little less, all depends on the quality of the cells.

If the battery is a High Voltage Pack, lets say it says it is 6000 mAH, that is at the rated voltage. Which for most LiHV packs 7.8 volts. For a standard Pack, that is 7.4v.

If the charger is set to 7.4v, which is the maximum allowed by most racing sanctioning bodies, the total mAH will be closer to 5000-5200m at 7.4v, even though it says 6000mAH at 7.8v. Lower Voltage = Lower Capacity.

The reason we run high capacity batteries in stock racing, is so that we experience less voltage sag over the duration of the run time, which is through the middle of the pack, for the greatest consistency of power output. Because in stock we cant run boost timing to compensate for voltage sag toward the bottom of the pack like you can in Mod. Which is why you see Mod guys running smaller 3700-4200mAH low profile packs, as opposed to the 5000-6000mAH full size packs in Stock.

The second part of this problem is the bottom end of the pack. You cant drain a Lithium based chemistry battery pack to Zero. There is a Low Voltage Cutoff (LVC) for LiPO's, where if the voltage dips below a certain point, there will be irreparable damage to the cells, and possibly even to a point where the cells cant be recovered to a usable state by trickle charging them. This is also a condition where you can puff cells as well. So even though the pack had hit LVC on a Discharge cycle, it wont take "6000 mAH" back, its not like a NiMH cell. It will probably be something closer to 4500-4800 mAH of charge to top up to 6000mAH of capacity at 7.8v. And if it is set to a lower standard voltage, like 7.4v as opposed to HV voltages of 7.8v, it would be more like 3800-4000mAH of total charge taken, making the total capacity around 5000-5200mAH, because the pack is only charging to 85ish percent of its total capacity at that lower 7.4v voltage.

Unfortunately finding out honest battery info in this hobby is somewhat of an easter egg hunt. No single vendor really explains it in any clear cut way, and you have to research and piece information together to understand what is going on in plain English. So hopefully this helps you to understand what is going on with your batteries a little better, and helps to answer your questions.

OffRoadJunkie

iTrader: (9)

It's nothing to get worried or stressed out about. Unless you're a really good driver who rarely crashes, you lap times won't show a difference worth mentioning. Once you get up with the big dogs, that's where you will looking to squeeze every bit of power to get more speed. For now, purchase what fits your budget and have fun. An HV battery will have quite noticeable more power, but do you really need more speed? 6000mah more than enough, regardless of what class you're running. Of course, unless your a pro in modified class on a really large track.

the rc guy

you can buy this meter..it might give you the info we all have tried to relay to you.

LiPo ESR Meter Mark II - ProgressiveRC

Pistol123

Here's a link to a good guide I read when I got back into the hobby and needed to understand Lipo's. It might be a little old now but it should be sound advice still:

https://www.msuk-forum.co.uk/forums/...ated-march-10/

GerryH

iTrader: (26)

OP, Your Zee batteries are HV, so unless you're charging to 4.35v/cell you won't see the full rated capacity. Think your Protek is also HV. Also given that Zee and CNHL are Ebay/Amazon specials, I suspect you're not getting the best quality, consistency or advertising honesty in these brands.

You didn't mention what voltage you were discharging to. If you're testing capacity, you probably need to go down to 3.4v/cell.

Don't necessarily need to know what the battery capacity is for racing. As BigBuck mentioned, it's all about what voltage your battery will deliver over the course of a race. And for offroad, voltage sag on hard acceleration is very important. Think coming out of a turn to a double jump. Can the battery provide enough punch to clear the double, or do you need to single/single?

themountain

Wow...easy with those words , fellar !...I cant speak for Zeee lipos but CNHL are top notch , they are in the same category than Tattu, gensace, etc.