Battery Question

[RT]

Hi Guys,
i got 2- 6 volt/4 ah sealed lead calcium batteries that i want to hook in parallel, witch will give me 6 volts / 8 ah . this is to be put in a home made rc boat. i dont know nothing about the reciever and motors as it was some guts from an old submarine rc , could this burn out the reciever or will it only draw the current that it needs. or do i need to put some kind of current limiting circuit in.will also have some led's in there as well.some blinking some not..

Also what kind of battery charger would i need to charge them up with as far as voltage and current...........once again *THANKS* for any and all info !!

 

[Styx]

It will only draw as much amps as the circult impedance will allow

You say it is 6V - if the equivelent load is 1Ohm then 6A would be drawn

If the equiv load is 1kOhm then 6mA will be drawn from the battery

 

[Russlk]

The load will only draw as much current as it needs, so you don't need to worry. To charge the battery, use a regulated power supply of 6.8 to 7 volts. A current limit would be nice, to avoid overheating the battery or the power supply.

 

[RT]

cool thanks for that info guys
also on the charging for the batteries iv'e got 2 wall adapters that are ..1 is 6 volts 700mA
and one that is 6 volts 500mA will any of these work to charge the batteries?
;THANKS ;

 

[RT]

Sorry Guys
1 more ?
is there a mathmatical way or some reliable way to tell when the batery is fully charged.

 

[stevez]

Take a look at the data on a MAX713 - it's an IC for a NiMH battery charger. In there is an explanation of how things work for an NiMH battery. You'll see that as you expected, it's not just the peak voltage. I'd be willing to bet that similar attention must be given to your battery.

I do recall reading about batteries and what methods can be employed to get the most out of a battery - which requires that they be optimally charged. Do a little googling and you'll likely stumble on to something. Maybe Maxim makes an IC for lead-calcium batteries - and you'd find what you need there.

 

[RT]

cool thanks,
but im thinking that i have a lot of wall adapters that iv'e saving for some time and this would be a good way to satrt using them if possible . if not then i was planning on just buying one for it ,as i belive for me this will be more feasable, just to many projects for me to keep adding on rite now.....THANKS for the info and as a last resort all go that route..