Field Charging Help

[Pilot Ben 28]

Hi All,

I need to get a proper field charger for my rx batteries and lipos too and wondered if anyone could point me in the right direction as regards to charger and battery?

Or maybe share their setup?

I understand the battery I need is a standard car battery that I could pick up from a garage for £10 or so? I think this can be topped up once a month?

I still use an £8 hobbyking lipo charger so I don't really know much about this topic

B

I also don't know if there is a charger that can charge rx battery and lipos or if I need to get two separate chargers for each battery type?

[Lofty 5]

Pilot Ben said:

Hi All,

 

I understand the battery I need is a standard car battery that I could pick up from a garage for £10 or so? I think this can be topped up once a month?

 

I still use an £8 hobbyking lipo charger so I don't really know much about this topic

 

B

Standard car battery would most likely cost you way more than £10, more like £40+! Most of them come with a floating charge indicator...e.g if you can see the green you are ok, if you can;t charge it up "some turn Red"

Or just play it by ear......work it out in your head how much you have used the battery for charging other batterys....

The higher the Amp hour of the battery the more you can charge from it.......but they do cost more and get heavy er etc etc So a 75 Amp hour battery could charge 75 x 1000mha battery's.......or there about's!

But the more you charge from the 12v car battery the lower the voltage of the battery its self.....so you will not get 75 full charges at all........

Also what type / voltage battery's do you want to charge, off the 12 car battery.....plays a big part of it as well! E.g good luck charging 5+ cell Li-Po off a car battery.....

I had to use a 12v petrol generator with the big stuff.........or lots of small stuff with multi chargers running!

Having said all that, if you just want to charge 3 / 4 cell Li-Po's and 4 / 5 cell RX,TX battery's then a standard 12v car battery will do!

When it comes to chargers, make sure you get a charger that is AC / DC.........so you can use it from a wall socket or a power supply and 12v battery! A lot of the chargers are the same, but come with different company stickers on them!

I am not going to talk about HobbyKing, someone else can! But if you want a standard AC/DC charger from the UK shop then something like this :-

http://www.logicrc.com/?s=c:0,c:40,c:40-30&ItemId=O-FS-LX60BP or

http://www.ripmax.com/Item.aspx?ItemID=O-IP2851/EUR&Category=O0150

Not saying buy one of these, the RipMax one is £90, lol wtf! But this is the type of standard charger, that most people have!

These are also very good, I've had a few......but only 12v DC

http://www.sloughrc.com/default.asp?WPG=SRCM_HomePage1&itemid=4402930

P.s The more bells and whistle you want in a charger the more its going to cost

[Pilot Ben 28]

OOnly 3/4 cell lipos and 4/5 cell rx batteries. I do like the fusion charger

[Lofty 5]

Pilot Ben said:

OOnly 3/4 cell lipos and 4/5 cell rx batteries. I do like the fusion charger

I only have 1 charger now, and its the Pro-Peck sticker version of the fusion charger....which is the same! Its not the best and its not that bad......will do anything an avg. RC flyer needs!

Most good model shops would discount that price anyway, "maybe"! But also you may be able to find the same charger at HobbyKing as well!

A lot of the in-side parts are the same as well, even if they have different looking outer body's.

Lots of people at the field have HobbyKing chargers, so best to talk to them....

[Bravedan 106]

Go to a car battery shop and plead poverty, they should if you tell a good enough story go to their recycle pile with their load tester and find you one that can take the very low by comparison discharge a LiPo charger needs. Remember, a car starter motor on a cold morning might needs 100 amps discharge, you need FAR less and so a relative "dud" is OK!! I have just replaced (with another throwout off my own car!) a battery I was given six years ago.

I bought a tiny electronic charger that stays on 24/7 and even conditions it at night when it senses the need, More recently though I have been using a high capacity LiPo to start my engines and this would charge the plane LiPos for most of my fleet, more than enough for a session. ( I don't as I have enough cell packs)

[Lofty 5]

Yep that is another way of getting a car battery! I used also used my old car battery's as well!

[Pilot Ben 28]

I do like the wifi module http://www.wheelspinmodels.co.uk/i/254383/

[Pilot Ben 28]

But is that way too expensive for me? I really do like it because with the wifi bit, the charger is really safety orientated, IE perfect for me

Overlander also do a basic advanced charger - http://www.wheelspinmodels.co.uk/i/237607/

The wifi charger - http://www.wheelspinmodels.co.uk/i/254383/

Wifi bit - http://www.wheelspinmodels.co.uk/i/262233/

What do you all think? Is the more expensive charger too expensive? I kind of want to buy it now and have it for years, like my 3 year old £4 hobbyking lipo charger

[Bravedan 106]

And this charges things better HOW??

It's an application desperately looking for a use!

Better that the design and money invested by the builder is spent making it safe and secure and robust.

Oh, and I don't like it...........................

[Pilot Ben 28]

[Emay 2]

Have a look on this: https://bmfa.org/class1/id/33979

or this: https://bmfa.org/class1/id/33977

[Pilot Ben 28]

The first one I won't buy because the seller can spell lipo properly

The second one I do like

I don't know what I quite need ! I just like the Overlander because I'm pressed for time to charge stuff and it charges two at once.

Would you say that the Overlander charger(s) are overkill? IE am I looking at something that is stupidly priced or is that around the price of charges that you all have/use?

[Bravedan 106]

OK, Joke over.....................

I have over 20 chargers (plus ten more that do NIMH only!), from £100 plus (AC/DC Graupner Ultramat 16) to less than £25 (12v X Charger B606). I'm often using five at once on LiPo.

NONE are multi-chargers and frankly as an engineer I would never buy one, as a basic engineering premise is "never put all your eggs in one basket".

While Lofty has advised AC/DC, a large slice of mine are small DC only ones. These are powered from small JPerkins PSUs which provide 12v @ 10A, so several chargers can hook onto one PSU (I have three of these PSUs, same thing, redundancy!). This also gives flexibility and is a cheap way of doing it. The chargers can be removed and taken anywhere off mains to be fed from a car battery or a high capacity LiPo. I also have a Sakura Car Starter, a tiny hand held unit that can start a near frozen not run for months 7.5 litre engine (as I have done just that with it!!). This is an emergency power supply both for charger feed and for engine starting!

In principle though I do not charge LiPo at the field, I carry sufficient packs to not need to.

Which Charger is "best"? Well absolutely not the expensive "name" Graupner, which despite its computer interface and supposed sophistication has an awkward menu system, difficult to read display, and worse, fails to do the job reliably, often ending LiPo charge crying wolf on high voltage with no measurable reason why! (and others with one have similar!).

Before I answer my own question, there are two basic types of chip/circuit/firmware used in LiPo chargers. One has Cell Capacity in mAh as one of its inputs, the other only charge current and cell pack voltage only. The former is in theory safer but is more awkward to handle when charging packs in parallel (which I do with small 1S, as returning from a school club session I might have 30 plus to charge!!). I use balance extension leads from the cheaper chargers so the battery can be more remote from the charger.

I actually like the simple and cheap AC/DC charger sold with a wide number of seller names on its front, the most common being "Intelligent Battery Manager" with a green label. On turn on, it and all the other "branded" ones are actually all the same, being a "G.T. POWER A606-D".

Second (though capacity measuring) comes the Fusion Elysium L60B Pro of which I have two. They are quiet in use and harder to "miss set".

Dave (having just completed charging nearly 100 NIMH!)

[Bravedan 106]

P.S. - Why do Chargers have such ungainly awkward STUPID names??

P.P.S. - If you had a decent charger, why would you sell it?? Answer in most cases, because its NOT a good one!! From someone you know, maybe, otherwise, no way.

[Pilot Ben 28]

Thank you Dave I'll take a look at the fusion charger. The only reason I'd get the expensive overlander one is because I'm lazy and that would be my charger for the next 6 years.

As regards to DC or AC/DC, most of the chargers that I'm looking at are AC/DC. In fact I've only seen on DC only charger despite looking at quite a few chargers

B

[Martin 0]

I've got several chargers, but only two brands. I've never bought any of the big-name RC brands (Ripmax, Graupner, Overlander, etc), so I don't know what they're like. The reason for having so many

In the order I bought them, I have:

• A GT Power 200W charger that lives in my transmitter case (since there was a space in the flight case) but rarely gets used these days. This was my original charger. It's DC input only, and I also have a 200W mains PSU for it, which never gets used these days as when this charger does get used it's for field charging.
• A GT Power "606-D" 50W charger with mains or DC input, which never gets used. The reason I bought this is that the 200W mains PSU I had for my first charger had a very noisy fan, although the charger itself was silent other than when discharging. However, this charger does have an internal fan, which always runs when on mains power, so was actually more noisy than the combo! Additionally, the fan is actually noisier than it should be (sounds like a bearing problem).

A GT Power "X-Drive" 6 4-output charger (yes, I know Dave's opinions and to be honest I would agree but didn't think clearly enough when I bought it). This is actually the one I use most often for charging Tx and Rx batteries. If I were doing this again I wouldn't buy the 4-output charger but instead buy multiple separate small chargers, which were only about £20 each on Hobbyking last year (presumably more now due to the current state of the British Rouble). In any event, the 4-output model is less capable than 4 separate units (for example, not all of the ports support temperature sensors), yet the price is always barely less than 4 separate ones. A Revolectrix "Cellpro Powerlab 6" which is my main charger for LiPos. This is an expensive luxury, but it's easily the best charger I've ever used. It has lots of nice features that cheaper chargers don't, including the ability to do regenerative discharge of batteries under cycle (so rather than having to slowly discharge the battery through a resistor and waste the energy as heat, you can charge up the source battery as fast as that can handle, which means you can cycle and test batteries under more realistic loads). It has PC software that allows you to graph the performance of your batteries over time, measure internal resistance, get an accurate estimate of capacity remaining, and so on. It's rated up to 1000W which is far more than I will ever need (and actually needs 24V input).

If I were looking to start again and money were no object, I'd get the Cellpro again. If I were on a budget, I'd get one of the GT Power or related clones (Turnigy do a range that seem almost identical, as do others). If you only have one it's worth trying to get a higher-rated one (more than 50-60W, like say my 200W one) as this allows parallel charging of LiPos, which is the best way to quickly charge multiple LiPo packs with the same number of cells.

The reason I got the 4-output was to be able to charge multiple different packs at the same time (i.e. Tx, Rx, glow stick, etc), as I prefer to charge nickel batteries at 0.1C rate, which takes a while! As noted above, if I were doing this again I'd buy several small cheap chargers instead, giving more flexibility.

If you want the mains input GT Power charger you can have it. I never use it any more and I can't see when I would. The fan is noisy but the charger works. I had meant to list it on the forum Buy & Sell but never got round to it.

As others have noted, a second-hand car battery makes a good field-charging power source. You can use your LiPo charger to recharge it if you have some sort of mains power input. Be aware that most car batteries are not designed to be discharged more than about 15% (so a 60Ah battery is only really designed to have about 10Ah taken out of it before it's recharged). Going further than this (and in particular leaving the battery in a partially-discharged state) will shorten the life of the battery. Then again, if you got it second-hand for £10 or so then you may consider that it's fine to do this and just get another when it won't hold an adequate charge any more.

If you have a charger with only DC input, an old laptop PSU makes a good power source, especially if you can find one with a standard type of plug like one of the coaxial DC plugs. Check your charger's rated input voltage - many can go to 15 or 18 volts and some even higher, and there are plenty of laptops that use PSUs around the 12-18V mark. Many laptop PSUs will put out 80-90W which is more than sufficient for a small charger as it can't draw more than that anyway. These are usually fanless, which is good since you will obviously want to be in the room with your LiPos while they are charging! You may need to solder up a suitable adaptor lead - Maplin sell coax sockets in all the different sizes (measure the plug on your PSU before buying the socket). I also have a GT Power 15V PSU which I bought with one of my chargers (probably the 4-output one), which is basically an unbranded laptop style PSU. eBay is also a good inexpensive source of this type of PSU - they are sold as aftermarket replacements for older laptops. You may even find something in a car boot sale or the like, or you may have an old dead laptop, LCD monitor, etc kicking around at home. Note that the small PSU-in-plug type adaptors are very unlikely to put out enough power!

[Martin 0]

martin said:

If you want the mains input GT Power charger you can have it. I never use it any more and I can't see when I would. The fan is noisy but the charger works. I had meant to list it on the forum Buy & Sell but never got round to it.

 

Do you want this?

[Pilot Ben 28]

What does it charge ? IE just lipo? I have ordered a £40 over lander charger so if you can sell it sell it but if not I'll buy it off you?

[Peter Royall 47]

did u get a car battery Ben?

I have one to give you if you want it.

Let me know.

You will, of course, need a car battery charger!

I bought a charger for model batteries at Old Warden last year, it charges Nicads/Nmph/ Lipos and burgular alarm type batteries, IE all I need. It was brand new and was £35.

Let me know about the car battery.

Oily