On Sun, 25 Sep 2011 22:50:04 -0500, Steve Barker wrote:

On 9/25/2011 10:37 PM, Jules Richardson wrote:
On Sun, 25 Sep 2011 18:37:48 -0400, Richard Trethaway wrote:

I've found that batteries dont last as long if they are mounted in
something that vibrates a lot like your average cheapo big-box junk
lawn tractor.

Interesting. What actually causes them to fail? (I mean the vibration,
yes, but what's the actual process within the battery that results in
them no longer working?)

cheers

Jules

in the case of vibration damage, the lead plates (which are kind of like
screens) physically break and lose connectivity with the adjoining cell.

Aha, thanks; I wasn't seeing how it'd really make a difference (and I
assumed the batteries would be built to withstand it).

In the case of winter abuse (not keeping it charged in winter) the
dead battery will freeze and the resulting "heaving" of the plates will
break them.

Yep... as mentioned in my other post, that's part of the reason I don't
bother with a battery on the tractor - I can't be bothered keeping it on
charge over the cold season (which is a long time up here in MN :-)

Overcharging (common with small cheap charging systems)

Now that did cross my mind - I can well believe that cheaper tractors
don't have the kinds of charging systems that might be present on the
more expensive ones, and that might be responsible for early failure; I
was just surprised that the vibration could play a part, too.

Maybe it's worth putting a piece of rubber mat, mouse pad, or something
like that under the battery to help dampen the vibration...

cheers

Jules