Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Batteries & Chargers => Topic started by: regiment on March 17, 2009, 12:59:09 pm

Title: battries
Post by: regiment on March 17, 2009, 12:59:09 pm

hi all  i have two 6 volt 4 amp sla batteries  if  i put them in series will i get as much running time as 1 12 volt 7 amp  hope some one can understand thanks. all you sparks out there 

Title: Re: battries
Post by: DickyD on March 17, 2009, 01:17:37 pm

Hi Gordon you should get a longer running time at half the speed I believe.

Now wait for the technical replies you wont understand

Title: Re: battries
Post by: Peterm on March 17, 2009, 01:39:37 pm

Keeping it simple, you should get 12 volts at 4 Amps.  Pete M

Title: Re: battries
Post by: andrewh on March 17, 2009, 01:40:17 pm

Gordon,

You have two 6V 4AH batteries.  If you connect them is series (plus to minus betwween the batteries)  you have 12V (2 lots of 6V) and 4AH (not amps, Amphours)

So you will have about half the duration of the 12V 7AH battery.

You two cells in series can (roughly ) supply one amp for 4 hours, wheras the 7AH can supply (roughly) one amp for 7 hours
however your two will weigh about half as much - actually 4/7ths as much.

Now if you run them in parallel (both terminations plus to plus, minus to minus) you will have 6V and 8 AH so you can take (roughly) one amp for 8 hours (but at 6V)

Clear as mud?
andrew

Title: Re: battries
Post by: DickyD on March 17, 2009, 01:43:48 pm

Sorry Gordon read your question wrong my answer is for wired in parallel.

Positive to positive and negative to negative. :embarrassed:

Title: Re: battries
Post by: regiment on March 17, 2009, 03:14:56 pm

thanks  all of th e brainey ones on mayhem  now i know i can get nearly two hours on the lake  ta

Title: Re: battries
Post by: regiment on March 17, 2009, 03:19:30 pm

dickyd thats your fudge gone to the dog

Title: Re: battries
Post by: regiment on April 12, 2009, 02:14:42 pm

i have a sa 10001 ni mh s c 7.2 3000mah battery been used a few times so i have been told  now how long will it take to charge it up from a pro peak 2500 charger/ another daft one what running time will i get useing a deans kestral in a revell corvette no more silly questions today   except anybody  like to move down to cornwall then i would have some one to ask when i go to the pond  :-))

Title: Re: battries
Post by: DickyD on April 12, 2009, 04:04:08 pm

Hi Gordon, I think you might be overdoing it with a Kestral motor and a 7.2V battery.

That is what I have in my 1:40 scale PT boat and that planes.

I have the Deans Kyte motor in my corvette with a 7.2V 3700mAh battery and I havent run it down yet.

Title: Re: battries
Post by: malcolmfrary on April 13, 2009, 12:41:04 pm

If the corvette is just run to look like a corvette rather than an S-boat, whatever the motor, it will pull about 1 amp at 7.2 volts, which gives pushing 3 hours, probably longer than the TX battery.