Electric mower battery

 Got a dumb question.... I have an electric mower that uses two 12V lead =
acid batteries wired in series to give 24V. The batteries are marked =
18Ah.  Cost is around $100 for one 12v, or $140 for 2 in series, =
including shipping.

For the same money or less, I can get two std 12v car batteries and end =
up with more amp hours to boot, which would be good for a mower.  =
Heavier to push around, but that's not a problem.

I don't know nuthin about how amp-hours work - reckon this would be a =
good idea?  Anyone had experience with this kind of thing before?

Bob

 

There are two basic kinds of batteries like that.  One is for starting  cars
and gas lawn mowers.  This is for a short usage of high curret. The other is
for long rime running such as your mower.  While you may be able to use one
in the place of the other, it is not recommended dfor long battery life.

The amp hour rating is very simple.  It is the ammount of current in amps
that you are using multiplied by the number of hours the battery can be
expected to deliver that current.  If you look at the motor , it will state
how many amps it will use.  Say it says 3 amps.  That means that if you have
an 18 amp hour battery you should be able to run it abour 6 hours.  If the
mower takes 9 amps, then you can use it for 2 hours.  While the math is
exact, the more amps you use, often the shorter the real usage becomes.

Often the long usage batteries are called marine batteries.  That is for
running the electric trolling motors.  For your usage, ask about them.

 
Thanks, Ralph.  Good info.  I kept searching and found some 12V 18Ah =
batteries in the $30-40 range, which is more reasonable.

http://www.tripleibatteryproducts.com/  (Website is off line right now.)

 
As Ralph said, most important is that you get the right kind of
battery.  I'd
put them in 3 categories:

1 - Starting batteries, this is the typical auto battery.  They are
designed to
give high current, but not intended to be discharged much or often.
If
you fully discharge it regularly and especially if you leave it
sitting around
discharged, it will cut it;s life very short.

2 - Deep cycle batteries, this is what you have.  They are designed to
give
reasonable current and to be repeatedly charged and discharged.

3 - Mixed use batteries that combine the features of 1 and 2, but
aren't
as good at either.


I'd be careful with the marine battery designation.  There are marine
batteries of all 3 types.   The main difference marine brings into the
equation is that they are built to withstand getting bounced around
more than say an auto battery.  marine trolling batteries would be
deep cycle, while marine starting would not.

I'd also wonder how two car batteries could fit a mower?  Is this
a riding mower?   As Ralph said before selecting an alternate battery
you need  to make sure it's deep cycle and get the capacity
right.  Besides that, I'd determine the basic battery type you have,
ie is it lead/acid, gel cel, etc.

 

As Ralph said, most important is that you get the right kind of
battery.  I'd
put them in 3 categories:

1 - Starting batteries, this is the typical auto battery.  They are
designed to
give high current, but not intended to be discharged much or often.
If
you fully discharge it regularly and especially if you leave it
sitting around
discharged, it will cut it;s life very short.

2 - Deep cycle batteries, this is what you have.  They are designed to
give
reasonable current and to be repeatedly charged and discharged.

3 - Mixed use batteries that combine the features of 1 and 2, but
aren't
as good at either.


I'd be careful with the marine battery designation.  There are marine
batteries of all 3 types.   The main difference marine brings into the
equation is that they are built to withstand getting bounced around
more than say an auto battery.  marine trolling batteries would be
deep cycle, while marine starting would not.

I'd also wonder how two car batteries could fit a mower?  Is this
a riding mower?   As Ralph said before selecting an alternate battery
you need  to make sure it's deep cycle and get the capacity
right.  Besides that, I'd determine the basic battery type you have,
ie is it lead/acid, gel cel, etc.


Thanks, Trader4.  Yeah, these small 12v's are 5-10 pounds each.  Two car =
batteries would make the mower hard for my wife to push.  ;O)