bsparks

okay, just getting my hyper 7 out after a few years in the closet and have a few questions.

1. I have a few lipo packs from a blade cx. 7.4V 800mah. can I use these as a rec pack in my hyper? if so how much runtime can i expect from them?
could I run them in series to get a 1600mah pack? can I just hook up my 12v auto car battery charger to them.

2. I also have some NiMh packs that have been laying around for a few years. what is the lifespan of these packs? should I just trash them and get some new ones?
what about runtime on a 1600 pack? I have two 5995 hitec servos w/ failsafe.

3.how many packs do you take to the track with you? or just use the same one throughout the day and recharge as needed?

thanks... (BTW just kidding about the charger)

K_B

If you're gonna run lipo, you have to run a regulator to drop the voltage down to 6V . The max voltage input for the 5995s are 6V. You could run them in series, but for the trouble, you're better off just getting a new receiver pack I think.

If the NiMH have been sitting for a few years, they may be toast. Batteries self-discharge and if they sit long enough, the will self-discharge themselves to a point where they can't be revived. Mine sit all winter long and charge up fine in the spring. But anything longer than that could be detrimental.

Not sure on the runtime since I swap my packs out. I usually take two receiver packs per vehicle. I run one for qualifiers and one for the main. I wouldn't be surprised if I could get by on a single pack, but who wants to take chances, right?

youwish16

im guessing runtimes with a 1600 pack may be around an hour. not really sure tough cause i charge mine after everytime i drive it. you might want to look into a quick charger(i have a dynamite prophet and it charges 1600 pack in about 15 mins)

i have 2 1600mah packs(1 integy, 1 racers edge) and i have a 2500mah stickman pack for those long 45min - 1 hr mains

nurch

Not neccessarily true. I had left the hobby 5 years ago on a hiatus while I got my finances and career straightened out after I got out of college. Since this hobby was a money sink for me at the time, I had to put it on pause.

I had purchased a lot of things and left them fresh in their respective boxes. I also had a bunch of EPIC 3300 MAH cells (24 of them) that I reassembled, 6 i3 batteries I assembled, and some GP4600 batteries I put together. Mind you these have all been sitting for 5 years. After 5 cycles (10 minutes apart with peak voltage set at 5mv and charge rate at 5.00A on my Thunder Power 610C and cut-off at 0.9v per cell on my NOVAK SMART TRAY battery balancer), my batteries were back to life. Granted they were charging up to 430 mah, and some other low number, but on the 5th or sometimes 6th time, my batteries WOKE UP and started taking full charge.

They did warm up once they took their full charge, but nothing was damaged, AT ALL! I used the packs I built in a couple races already and they are working absolutely fine. I still use them aggressively and have not noticed any hinderances. They also discharge just fine as well.

What I have learned from this is that NiMH cells that have sat for 4 or 5 years still work just fine after you cycle them. If they warm up, they are fine. I know manuals say not to warm them up even an ounce or else they are damaged for life. I do not believe that. 6 races so far, my packs have never overheated again, and they are working damn fine.

K_B

There are always exceptions. Those are all quality cells. I have lots of GP3300s that have lasted me many years and I don't do any maintenance on them in the off-season. Many receiver packs use cheap generic cells. The rule of thumb is that if you're gonna leave a battery in storage for an extended period, you should charge it up to about 75% before putting it away. I just charge 'em up full (too lazy to monitor the packs for 75%).

Heat is a natural byproduct of the charging process. That's why many top-end chargers have inputs for a temperature probe. Generally speaking, a battery is fully charged when it reaches roughly 130 degrees. When mine are done peaking, I check them with a temp gun and they are all usually around 120-130 degrees. For receiver packs though, they should never really get hot because you should only be charging them at around 1-1.5A.

But this goes waaay beyond what you need to be concerned about with receiver packs. Long story longer, cycle the pack (charge/discharge it a few times) and it should come back to life, like was said. But, it may not if it's a cheap-o generic pack.

dustineich

and the HITEC 5955 servos will run unregulated... they will take 7.4 volts as they are rated for eleven volts... the HITEC servos use the same boards as their robot servos... you will need to check your receiver though... ditch the NiMH get e new one its only 20 bux...

INTEGRA

WHAT!!!!! Hitec's are NOT rated for 11 volts....spec sheet please ?

THE only servo's on the market that are labeled safe for direct 2 cell are KO and the soon to be released HV JR's.

mabuecker

My Feedback: (8)

lol lol i thought you were serious about the charger. integras not regulated are ya?

man bsparks id save and go lipo. good things happen with'em these days. with my regulated 2s lipo I run about 2 hours and not hardly put a dent in it. once you get one set up youl be very pleased. just seems like the nickel packs, unless your used to them can be a pain. much easier to run lipo and basically be unlimited for about $50&a cheap 2s balance charger

INTEGRA

huh ?[sm=confused.gif]

mabuecker

My Feedback: (8)

i re read post and then read the end lol

integra. as far as i remember your not regulating lipo. i just wondered.

INTEGRA

I run losi regulator's on both buggy and truggy.

mabuecker

My Feedback: (8)

rite on. same here. some guys take the chance, just not worth it. yer one of the people that got me to go lipo. i never thought i would. now i cant amagine anything else. in the long run they are much greater.

INTEGRA

and some people doubt my crazyness. [sm=lol.gif]

mabuecker

My Feedback: (8)

lol. lipos are crraaaaazzzzy&convenient. you seem to be making upgrades the right ways to save$&time before others, so i listen to yer stuff