Ceros batt ideas

Ceros is still in many pieces but plans are in motion would like to gauge all hw roboters ideas on this problem, how much power is drawn in an average fight.

lipo batt packs 22.2v 8000mah from hobby king £80ish
2x 12v 5000mah nimh packs (35amp draw)very low £90ish
sla £** all sizes shapes and prices

so the problem, i want to use lipo batteries but the autocut off function i would build in myself in the control line. or just use two lipos togeather ie 16000 mah

but dont really wont to have to baby sit them in pits just sounds boring, i like to walk and chat :proud:

any suggestions

If your want to run Lipos you will have to baby sit them in the pits. If your running Perms, i wouldn't touch 95% of the Lipos on Hobby King, go for the Optipower (especially with the 30% discount available) ones.

I uae about about 4 amps per fight , most I think has been about 6 amps, there are some a123 batteries for sale on here aswell, the optipower 50c 100 burst are the lipos you need, 10 amps of them.

Bullfrog uses the Zippy LiFePo4's. 4 packs of 5S 4200mAh. Resulting in 33V 8.4Ah.

No babysitting these babies, seen as SLA's concerning safely and such.
Also, after a full fight, we are exactly from full charge to storage charge. Meaning we just used up 4 to 4.5 amps.

If you want to go 24V or simular, you can go 6S, meaning you have a large choise of acceptable chargers with a normal pricetag. Otherwise you could use 2 times 4S, to get 8S.

We're planning to use Zippy LiPo 4S 8000mAh, in a simular configuration ,29.6V 16000mAh for another heavy. And with 640A burst, and planning to limit the fuse to 400A, we're not worried.

LiPo Bunker and suitable charger is already sorted out, as well with real time telemetry on the batteries, we're playing it safe. Babysitting these to be charged. @2C rate, we're talking real amps to be pushed. A total of 950W, that means big powersupplies and expensive chargers. On the other hand, in 20-30 minutes bleepedybleepedybleepedy Ready.

And the fun bit is, still cheaper than a set of new Hawker Oddysee's or SBS with a suitable charger. Easy kilo's to reap if you ask me. Low hanging fruit indeed.

LifePo4's look good but not sure i would trust turnigy batts,use them in my model cars but prob not on the perm motors, custom pack with these maybe. see link
http://www.all-battery.com/Tenergy3....ell-30080.aspx

please comment guys more then 3hw out there

thanks adam

or these look good not sure on max draw would expect 50ish amp
http://www.all-battery.com/20pcsofdP...teries904.aspx

Were going to run Mute and Bonk on the Optipower batteries, seem pretty good and as Alan says nice price with 30% off

These are ones weve gone for http://www.optipower.co.uk/Catalogue...cat=131&cnode=

We currently use the A123 in Mute and they do fine with the LEMS but the lipos will be much better

adz600. I don't see the problem in itself to use the Zippy packs. Hobbyking has a reasonably working warranty setup, if a pack is faulty at arrival, the warranty covers it. It just takes a LiPo tester before you do anything with them.


We have a reasonable amount of Hobbyking LiPo and LiFePo4 batteries in use, in robots and RC cars. All it takes is some charging discipline and regular check-ups.

its a good point, just my turnigy in my hpi blitz goes out of ballance. but might give them ago they are cheap.
just looking at all the options before spending cash.

Kronic will be switching to the Optipower ones Mute are using.

That is why we opt for the Hobbyking products. Affordable compared to European resellers.
After all, in most cases, the stuff is just rebatched premium quality controlled product from the same factory somewere in China.

Your using lems in a high class of heavyweight... Don't cheap out and use rubbish lipos you will only regret buying... Most hobbyking lipos are indeed re branded cheap stuff... Optipower / thunderpower packs are in a different class... There's a reason people in other hobbys such as rc heli's etc stear clear of hobbyking lipos! Eventually people on here will learn to do the same.

With a RoboteQ AX 2550 in Ceros, the max amp draw is not even close to the "hobby-amperes" of the more affordable LiPo's or LiFePo4's,with enough Ah capacity to keep a heavy going for a full fight. (not counting damage and shorts, what should be solved by a well chosen fuze.)
For example. A Zippy 4200mAh LiFePo4 is rated 30c cont 40c burst. 4200mah is on the very very low end of the Ah needed in a heavy. So 2 in parallel to get 8400mAh. Even taking in account the "optimistic" amps you can draw from it, and degrading those to 20C packs , you still have 168A to play with.


Team RCC is happy with the Zippy LiFePo4's in Bullfrog. What can I say more?

I'm willing to bet that over 80% of our RC pilots on the airfield I fly at use Hobbyking stuff, lipos, ESC's, motors and all. The same is true of most of the RC offroad racers in the Truggy and buggy cups 1/10 and 1/8th scale. Most run either Gens Ace or Turnigy, and that is mainly because Zippy has only few hardcases at the moment which are mandatory at the races.

opti power look good, 5000mah 6s about £69 or flight power as used by big nipper not sure on the packs but, 4000mah 25c at £42.96
heard good things about flight power batt also

dont order from flightpower! they've ripped loads of people off and owe alot of people money... just ask callum...

any more ideas, optipower do look good just still unsure with high price, will defo use a lipo system just which one

I've just bought some optipower lipos for my heavy. One pack seems better than two of my old Nicads. I'm sure you won't be disappointed.

Can I ask.. everyone seems to want lipo, I haven't seen much mention of Lith-ion. Is that purely a weight consideration?

I've not investigated But I would guess commercial availability and current draw.

I believe that lithium ion is not allowed or mentioned in the rules, I enquired about them a year and a half ago and was told they weren't allowed.
However we are allowed lithium iron, which are the A123s a lot of people use.

Lipos are now allowed in Heavies. Lipos are being preferred, slightly lighter than A123/Lipofe4 but are much better performance.

There are quite a few Lithium battery technologies knocking around typically derived from Lithium Ion. Lithium Polymer (LiPo) and Lithium Iron Phosphate (LiFePO4) are what is allowed for use in fighting robots.

Although the modern, e.g. Optipower LiPo cells have better performance you do need to be more careful to charge them correctly and protect the cells properly. LiPo cells are less durable and puncturing them will result in fire. There are specific additional requirements when using LiPo cells and you do need to make sure they are sized correctly to prevent over-discharge.

LiFePO4 offer good performance and are safer and more tolerant to over discharge. However, when used properly, LiPo come out ahead.

Other Lithium batteries aren't really commercially available for our use and due to the safety concerns are not allowed.

Fantastic, thanks for the lo-down. Hope I didn't hijack the thread.

Quote:

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Originally Posted by Bacon Wizard

Can I ask.. everyone seems to want lipo, I haven't seen much mention of Lith-ion. Is that purely a weight consideration?

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Lithium Ion suffers from the same problem as NiMH compared to NiCd. High internal resistance, meaning a low capacity for current draw.
Also, I never found a source for them. Didn't look to hard either, as LiFepo4 and LiPo are readely available.

optipower it is just waiting for order info,

how good are hobby king chargers, currently use a high end rc car charger only does 3s lipo but was silly money and is great.

looking at multiple single chargers or 1 multi ,all the 4x6s look really cheap and have no memory function what a faf,
hk mega 300w 2x6s looks ok any other ideas or recomendations

thanks all

moved this 'ere post

Quote:

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Originally Posted by adz600

how good are hobby king chargers, currently use a high end rc car charger only does 3s lipo but was silly money and is great.

looking at multiple single chargers or 1 multi ,all the 4x6s look really cheap and have no memory function what a faf,
hk mega 300w 2x6s looks ok any other ideas or recomendations

thanks all

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I have the 4*50W Hobbyking Quadro and the 4*100W Turnegy, and I'm happy with those.

kane any update on optipower order info,
thanks