Charge 7.2v Stick Battery with 13.8v DC Regulater

[Naz]

Hi

Looking for some advise from guys who have experience or any feedback will help.

Right.... basically I have a DC Regulator lying around and I want to see if I can make some use of it.....

I've read hear and there that this is possible but not too sure if it can be done realistically.

What I want to do is charge a 7.2v stick battery using my DC Regulater - specifications are

 

Input Voltage                  2.30v - 50hz

Output Voltage               13.8V DC

Output Curent               7A Continuous

                                        10A 50% Duty Cycle

                                         12A   Surge

 

Fuse on Rear Panel       F 2A 250V

Internal Fuse                     F 1A 250V 

 

This is all the info infront of unit. 

 

If I need to buy something to regulate the amps or voltage so it doesn't cook or blow up my batteries, please tell me what i need exactly as I am clueless about this.

 

By the way the battery is for my roto start for my nitro truck so anxious to hear what advice you guys have to give.

 

Thanks a bunch in advance 

 

naz  

 

 

 

 

 

 

 

 

 

[Biggles' Elder Brother - Moderator]

Hi Naz, and welcome!

 

You're going have to hang on for one of the sparky gurus to show up - Tim or Danny for example. My guess is they will be around tomorrow morning - they are both "early birds"!

 

BEB

[Bruce Richards]

Naz,

 

Welcome to the friendly forum.

 

You could use one of these but I guess that's not what you are looking for.

 

Bruce

Edited By Bruce Richards - Moderator on 14/12/2010 15:01:38

[Chris Bott - Moderator]

Hi Naz and welcome.

 

I wonder if no one else is asking because they already know? But I don't, so can you expand on exactly what a "stick battery" is. Is it NiCad or NiMh or Lipo or something else?

 

It sounds like your regulator will be a great supply for a charger. But you'll need a charger that can be set for your type of battery. 

[Bruce Richards]

I assume it is something like this.

[Naz]

Hi guys thanks for your replies

 

Ok firstly HI Chris, 'Stick Battery' right.... pretty sure this is the correct terminology used for this type of battery but yes, sorry forgot to mention it it is a "NIMh" battery 7.2V 6 cells and yes Bruce spot on that's exactly right with a Tamiya connection.

 

If anyone is unsure about the type of battery I am talking about just click on Bruce's link. 

 

I totally agree with you Chris that this could be a great charger, but this is my dilemma in terms of settings for my type of battery, how can I do this?, unfortunately my Bench Power Supply (Regulator) doesn't have any adjustment dials or display so is it possible to buy something to regulate the charge for the battery etc??....

I have read on the net some charge on a bench power supply until it goes warm and then take it off, some use a 12V bulb to regulate the charge so it doesn't cook the battery, but this sounds all very sketchy to me.

So if anyone is a bit techie when it comes to electric's I'd love to hear your thought's on this

 

naz 

Edited By Naz Nawaz on 14/12/2010 13:37:13

Edited By Naz Nawaz on 14/12/2010 13:39:03

Edited By Naz Nawaz on 14/12/2010 13:54:03

[Steve W-O]

You need a constant current source, if you google that you will find plenty of easy ways to make one.

 

There are also dedicated ICs to make chargers with delta peak detection and over-temp shut down, short of opening one of my chargers, i can't remember the number. I think it was an max  something, it is about 5 years ago I made them

[Steve W-O]

It was a max712 or max713  or both. Seem to remember one was better for my use than the other. Maybe more will come back to me. Look those two up anyway.

 

Car bulbs will limit current, and will work, but it is very crude and open to problems if you forget it is on charge.

[Chris Bott - Moderator]

Naz you need something to control the current while it's charging, and something to detect that it's full. This is when the voltage stops rising and dips very very slightly.

 

In other words you need a battery charger.

 

Almost all of the ones sold by hobby shops these days require a 12V supply, which is the bit you have.  

 

The one Bruce linked to looks suitable but there are many more. 

 

[Naz]

Ah right!!.... thanks Chris for highlighting what Bruce recommended. Now I see where he was coming from.

This seems like a real neat uncomplicated and tidy solution

I like Steve's idea too but for me it's a bit too complicated in terms of part's, labour and sourcing and I don't like dabbling with electric's when I personally have no experience, I'll probably mess it all up.

 

So let me get this right.... basically I use my Bench Top for the mains supply and then plug my battery to the Power Charger to charge? - How simple!! 'Wicked'   

 

My other question would be I've just been on to ebay and they have some for about £20, do you think they will be any good? or shall I spend a little bit more for quality,reliability and a more recognized brand? 

Edited By Naz Nawaz on 14/12/2010 15:58:05

Edited By Naz Nawaz on 14/12/2010 15:58:58

[Bruce Richards]

Only you can make that decision Naz. It depends on how rich you are and whether you will ever use all the other functions on the charger I link to above and the capabilities of the charger you are looking at on ebay. All I will say is that I recommended that charger to a friend of mine and he was very pleased with it.

[Chris Bott - Moderator]

Or how about this one Naz? GT Power V5 again from Giant Cod, who send stuff out very quickly indeed.

[Naz]

Hi

Just looking around at different Balance Chargers and am coming across 50W/80W/150W and 200W, what factor does this all count for?

Will I be ok with just a 50W or the higher I go the faster it charges?

Also coming across 5A/6A/7A and 10A same question as above how does all this make a difference?

 

Thanks again in advance and sorry for my lack of knowledge

Edited By Naz Nawaz on 14/12/2010 18:41:42

Edited By Naz Nawaz on 14/12/2010 19:12:19

[Steve W-O]

Sorry, when you asked for more technical opinions, I thought you had an interest in electronics.

 

I use the "B6" family, they are made by different people (well at least they have lots of different names on them, probably all made by the same place) I have not found them to be inaccurate on lipo balance, all within 1/100V checked on Fluke meters. They range from £30 to £17 on ebay.

 

I use them for all battries, and I have charged 3300mAh car batteries, they go up to 4A so are fine for me.

 

I run them off a deep cycle leisure battery, but they would run just as well from your supply.

[Naz]

Hi Steve

With all do respect to you I initially did have a interest in electronics and especially in terms of upgrading/modifying my Bench Top, but I think you are too much of a whiz for me .

Your solution although was great scared me and I would of probably killed myself  (Lolz) trying to construct this without any guidance as I've never done stuff like this before. I was hoping for a simpler idea but I think this was probably me thinking without any concern for safety... and I use the word earlier 'sketchy'

 

So I think that the Balance Charger is a great compromise and a simpler solution for me which I've turned to like and I would of never of known about if it I never posted my question on this forum so i am very grateful to everyone's help

Edited By Naz Nawaz on 14/12/2010 20:17:58

[Steve Hargreaves - Moderator]

Posted by Naz Nawaz on 14/12/2010 18:40:40

 

Just looking around at different Balance Chargers and am coming across 50W/80W/150W and 200W, what factor does this all count for?

Will I be ok with just a 50W or the higher I go the faster it charges?

Also coming across 5A/6A/7A and 10A same question as above how does all this make a difference?

 

 Basically the more power you have the bigger batteries you can charge....for round numbers if we think about a 12 volt battery you could charge this at 4A on a 50watt charger (4 x 12 = 48 watts) or at 8A on a 100watt charger (8 x 12 = 96watts). These are theroretical figures however to illustrate the point ...a 50watt charger will ned a few watts to power itself so will never actually provide a full 50watts of "charging". The current values you have stated basically mean the same thing...Watts equals volts x amps.

 

It all depends on what you want to do with your charger.....50watts will certainly charge up your 6 cell battery quite nicely. I used a 50watt charger quite successfully for many years but have just upgraded to a 200watt unit simply so I can charge more/larger batteries faster....

 

Hope this helps....

[Naz]

Yea Steve that's great puts a lot into prospective.

 

OK I've been doing some hunting on the net and the best deals I have found seem to be on ebay and where as the better quality one's are about £30 - £40 I'm pretty sure that these deals are a good £10 - £20 approx cheaper than on the net. The down side is they all come from over sea's so will take a week or 2 to get here, but I'm OK with that.

 

I've added links below for you guys to see and would love your opinion on them and tell me whether you guys think they are worth buying.....

 

 

 

These are the one's I am looking at and I think they are great value for money, I've done some reading as well and they seem to be just as good as the expensive one's and to be honest I've spent so much money upgrading my truck i don't want to spend loads on a charger.

I've also put one of the B6 family charger as you recommended Steve but let me know what you think, this includes everyone as well

 

Thanks look forward to reading your opinion's

 

naz 

 

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[Bert]

Hello Naz

 

Simple way to do this

 

PM me an address and I will send you one of These chargers.

 

I have one I don't use and I can't be bothered to sell it, so if you want it you can have it.

 

Bert

[Steve Hargreaves - Moderator]

A great offer from Bert, Naz.......snatch his hand off!!!!

 

Can I have one too bert..........?

[Naz]

Oh WOW!!! 

 

What an offer that I can't refuse, I will PM my address to you  

 

Absolutely much appreciated Bert