battery question

[charlo 0]

Hi guys ! I'm totally new to rc and I wish to buy a tamiya kit, always wanted one when I was a kid. I'm just not sure if I should go lipo or nimh. I'm thinking getting a clod or a lunchbox. I've read as much as I could about lipos and nimh but it's a bit confusing. When a lipo is in storage mode on the charger, do you let it on the charger indefinitely to maintain the 3.6V ? If you want to run your model, can you just grab the lipo in storage mode and enjoy it or you need to fully charge it first ? As much as lipos seem powerful and better on paper, they seem like a lot of hassle am I right ?

Now for Nimh,, can you simply let the battery on the charger all the time and just hook it up to your rc when you wish to run it ? The main thing is that I don't see me "planning" to use the rc at a precise time of the day, sometimes I'll just feel like running it right now and be done with it. Mainly interested in buiidling the kit. So should I go lipo or nimh ?

 

 

[DeadMeat666 1675]

If you're buying a kit mostly for the build, then I think Nimh is the way to go. You can charge a Nimh battery fully and it will hold that charge for a few weeks so that you can 'grab n go' so to speak when the occasion arises. LiPos need to be in storage mode when not used, and will need charging to use, so in that way they're slightly more of a hassle.

[charlo 0]

okay but when lipos are in storage mode, do you disconnect it from the charger and them from time to time or simply let them connected to the charger ? Also, for your average 3000 or 4000 mAh lipos, how long to get them fully charged from their storage status, like an hour or so ?

 

If I go lipo, I'm getting a clodbuster otherwise with nimh I'll stick with the lunchbox. It's a big decision  ! ; )

[Matty36 267]

You should always disconnect from the charger once charged or in storage mode. Storage mode is less than full charge, so it would need to be recharged before use. I wouldn't leave a lipo fully charged.

It should take a good hour to go from storage mode to fully charged, maybe more depending on the charger and rating it charges at. If it's a 2s lipo, it needs to be balance charged.

[Mad Ax 9306]

If you are just getting into RC NiMH is probably best.  As others have said, you can leave a NiMH fully charged and it should have some power when you want to go out.  All batteries will leak a little bit of charge when left idle, but a new NiMH pack shouldn't leak much over a couple of weeks and if you do decide to top it off before a run it will only take a few minutes.  The best way to treat a NiMH is to recharge it again after use and put it away.

Over time you will notice your NiMH doesn't charge so well and doesn't run for as long, and maybe that's when you'll want to think about upgrading to LiPo, as by then you might have a better idea of when you'll run your car and be better prepared to get charged.  With that in mind, go for a deal that gives you a LiPo-compatible charger up front - a programmable charger will also have functions for charging your NiMH in the most friendly way so you get the best out of it.

If you do go with a LiPo then it's not massive hassle, just requires a bit of discipline - put the battery to storage mode after you've finished running it, then put it away.  It doesn't actually matter if it sits on the charger for days or even weeks - the charger will shut off once the battery reaches storage voltage and there should be no more significant leakage when attached to the charger as when not - but as with any electronic item it's best to unplug it when it's not being used.  And of course you should never charge / discharge a LiPo unattended, so you'll be there when storage charging finishes to unplug it and put it away, right?

Normal storage charge is actually a little above minimum voltage, so you can grab a storage charged LiPo and run with it for a little while.  I frequently do this when I need to test something on the workbench or in the garden.  Actually my LiPos give me so much runtime that I rarely need a charged one for any testing at home, I only charge my packs for races / away events.

[ACCEL 2014]

CAUTION:  

LIPO,s, LiFe, NiMH  battery heck any battery can be very volatile (yes when done correctly they're safe) Note: keep all  batteries in a Ammunition Metal Box with a 1/4" or 1/2" hole drilled into it (a lil' metal screen over the hole to keep the bugs out).

You need to read as much info and ask questions and research chargers about chemistry capabilities if you plan on charging different types in the future, most do All in One but need to be specifically programmed input for their levels, there has been a flux of more easily operated chargers  to hit the market as of late.

HiTec , Spektrum and a few more have gotten easier to use, so cost and your time to study will factor how easily it will be to charge these batteries with ease.

There's a lot of info and a lot of charger models and there's well this place.

Get a Volt/Ohm meter and or battery cell checker also, i always double check my batteries just for fun and helps keep me in the safe zone. I never rely on any one electronic device. Man made them and my house and vehicles are important to me.

 

 

[simalarion 2195]

And please  note if not alreadt mentioned the 3 main differetn plugs (Tamiya standard plug, Dean, XT60 and you also have Mini TAmiya plug but hav not seen it in use), My main problem now ( just learned the basic regarding RC battery) on Tamiya RC is what to do with the plugs. I am thinking for the future as my ESC (Quicrun 880) in Agrios support Lipo i will solder on XT60 plugs and use the Lipos on Agrios only and keep the nimh for my Buggys (Top-Force - The Grasshopper). For kids use i would say nimh only from what ive learend so far (heat problems with Lipo, more things to watch out for when charging). So if you have Nimh and going over to Lipo you would probably also need to change all plugs in cars (ESC) and have the same plug support on charger 

I have been waitng 1 month for my SkyRC B6 that is stil not arrived (through AliExpress), if that parcel somday should find its way to my door. Reason for ordering new Charger is to have better controll, i think this is for the best on  Nimh  (its a must on Lipo) also to expand lifetime and have better controll of the battery. For Lipo standard RC is 2s = 7.4 volt (some goes to 3s 11volt but as a newbie i will not go there), so the main thing when chargin Lipo is to go to the menu on the charger and choose Lipo and 2s then you can find out if the battery have as much mah as it says :). For Nimh you just choose Nimh and then the mAh vallue (3000 mah will be 3 & 5200 mah will be 5.2) then you can watch the dislpay and see if the battery really take as much as it say on the "thin".

For Lipo you will also need a safety fire bag, ACCEL mentiond Volt meter, i see many are happy with these:

Thats in Norwegian kr, so its only 2-3 GPB

[Juggular 4961]

6 hours ago, charlo said:

okay but when lipos are in storage mode, do you disconnect it from the charger and them from time to time or simply let them connected to the charger ? Also, for your average 3000 or 4000 mAh lipos, how long to get them fully charged from their storage status, like an hour or so ?

 

If I go lipo, I'm getting a clodbuster otherwise with nimh I'll stick with the lunchbox. It's a big decision  ! ; )

Yes, always disconnect. You don't leave anything plugged after the charger has done its job.  Lipo does not like high voltage, nor does it like low voltage.  At 8.4v, it starts to die slowly.  Below 6v, it dies too.  Charge or discharge too much, it will catch fire. 

That's why there is "storage charge" to keep it in the middle, like 7.6v.  You leave it disconnected, but it's not going to self-discharge as fast as NiMH.  It should keep the charge for 8-10 months.  If you are not using the battery, connect it to the charger every 6 months and do the "storage-charge."  Any amount of electricity you lost during that 6 months of inactivity, it would fill and keep it alive.   

I would do the full charge only on the day of running.  The charger will bring it up to 8.4v.  How fast it takes depends on your charger. At "storage" your battery is about 30-40% full.  Let's say it has self-discharged down to 33% in several months and your charger can do 6A.  If you have 3000mAh, that means down to 1000 mAh in storage, 2000 mAh more to charge.  6A charger means it will do 6000 mAh per hour: it can charge 2000mAh in 20 minutes.  

As mentioned, LiPo dies slowly at high voltage.  Use it in hours, not days.  If it rains, drain it.  "Storage charge" will discharge the battery down to 7.6v. Many chargers drain also, even though it says storage "charge"--they should call it "storage mode."  Mini chargers like iMax B6 discharges very slowly, but it's safer than using light bulbs.  If the sky clears, charge again.  It only takes half an hour to charge back up even if you have a 5000mAh battery.  

(Fireproof bag and LiPo alarm are cheap and useful)  

 

[charlo 0]

thanks a lot for all your info, much appreciated ! Seems afterall that lipos are not that much work. Might go with lipos then. I've read that people run clodbusters with the stock motors and 3s lipos, will that burn the motors pretty fast ? Are 2S fast enough to have fun with clods ?

[DrGoatboy 132]

If you are just going to run a lunchbox then you will probably find NiMH to be more than sufficient. I ran my lunchbox on NiMH for years, in fact I still do. You will get really long run times and zero hassle. Just charge the battery up, leave it, and when you fancy going for a drive pick it up and go! The batteries will last for years depending on how much you use them, chargers are cheaper too. Lipo needs a bit more planning and a bit more thinking about.

HOWEVER... If you think you are going to really get into the hobby and start running quick 4wd buggies or heavily modify a lunchbox you will likely get frustrated with NiMH and will want lipo eventually.

[Fabia130vRS 2098]

I did run mine on 3s 4000mAh. Much lighter then the 5000mah nimh I used to drive. 

[Wooders28 4719]

23 hours ago, charlo said:

When a lipo is in storage mode on the charger, do you let it on the charger indefinitely

You've already had answers, but, 

No, storage charge is a voltage that is between full and flat, and normally 3.8v per cell. This is because lipos hate being left fully charged, and can age prematurely, plus the risk of fire is greater, the more energy that is stored. You need some charge in the Lipo, as they do loose some voltage over time, not alot, but they do, a bit of a balancing act. So you leave enough charge in to allow for that, as if they go under 3v per cell, that's them damaged (usually, but you will get stories of charging them on nimh setting to get above 3v, then charging on Lipo,  to bring them back, I've done this, and the battery works, but it's weak and always a big difference in cell balance, so it's for the bin) 

14 hours ago, charlo said:

I've read that people run clodbusters with the stock motors and 3s lipos, will that burn the motors pretty fast ?

Mine ran for years on 3s with silver cans, and about as quick as a stock one will go without spending more time upside down. It's really low geared, so the motors don't really get stressed.

If you're going that route, the hobbywing 880 esc is a duel motor esc, with Lipo cut off (and good for upto 4s!?! ) 

 

14 hours ago, charlo said:

Seems afterall that lipos are not that much work

They are, but they're not (if that makes sense) 

Once you've got sorted with a decent charger, that'll storage charge, charge bags, metal storage (although I've never heard of one just randomly igniting, it's always when getting charged, or if they've taken a big hit), get your head around things, it becomes 2nd nature, they're not bad at all ,and the performance gains make it sooo worth it.

Low voltage alarms or a compatable esc are a must, they don't really slow down, like nicad/nimh when flat ,they just get less ,punchy (won't lift the front end on command etc), if they start to slow, it's usually to late.

[DayRider 311]

If I could give my opinion here as I have just started using lipo and before that nihm. The pro's for lipo are great power delivery and very light and the con's, you have to pick your time well to use them for e.g. you start charging up a power pack but the the weather changes and you don't end up going out,  then you have to discharge. Gutted!

Nihm pro's are went its charged and the weather changes its still ready for when it clears up and that extra weight they have are great for more traction in the damp.

If I was you get both, but I would start with nihm first just to see if you are going to get into it and if you do get lipo but when you buy your charger get an imax b6 so you are ready for when you make the change.

[Wooders28 4719]

5 hours ago, DayRider said:

you start charging up a power pack but the the weather changes and you don't end up going out,  then you have to discharge. Gutted!

Did that once or twice, and with the old Imax b6, it was a pain, with a discharge rate of only 1amp. I've since got a decent charger, with a 5 Amp discharge, and although still a pain, it's not a pain  that takes hours! 😂

I figured I'd ease myself into the world of Lipo, swapping all my old Nicad and Nimh to deans. Think I used each one maybe once after I'd ran Lipo......

Have a read, pretty much the got page for new people to Lipo 

 

https://rogershobbycenter.com/lipoguide/