It is really not a good
practice, why would you want circulating currents eating up
batteries until equilibrium is met?
Ford made the
decision to do it? They had their reasons.
For Me, I would have
never done it. And I worked for Ford Aerospace for a lot of
years. Yep, wonderful Newport Beach, Ca.
I did not to get in on
that decision, they probably would not want my comments!. It
is not the right thing to do?
I guess if it works,
OK? They have sold lots of trucks.
Just buy both
batteries when you change. Hope they are matched? $150 ea.
On 1/15/2018 5:47 PM, Jerry Gaffke via
You're right, it's
not a good idea to blindly parallel a bunch of batteries.
But it can work just fine if they are of the same size and age and
If one has more internal resistance, that just means the other one
will be doing more of the work.
However, if you connect them when not equally charged, one will
charge the other.
In some cases the currents involved while the charge states
equalize are excessive, far beyond
what either battery is rated for. Could easily have an explosion.
Something to keep in mind, especially with Li-Ion batteries or
large lead acid batteries.
Once the batteries in parallel reach the same charge state, there
won't be any
currents bouncing around.
I have several of LED headlamps I bought on the web.
Each has two 18650 Li-Ion batteries in parallel, they feed the LED
through a resistor.
I doubt these particular 18650's have any kind of over-current
protection, as the headlamps were quite cheap.
Use them all the time, work great. And keep their charge just
fine when sitting on the shelf.
We're off grid, I started out with used golf cart batteries,
wiring up multiple banks in parallel.
Around 10 KWH worth total, all having different histories and
If anything, any extra internal resistance due to aging would have
helped prevent excessive currents
if I had connected them in parallel without first bothering to
check if the voltages were reasonably close.
On Mon, Jan 15, 2018 at 04:14 pm, Michael Hagen wrote:
You do not want to parallel batteries, difference in
internal resistance will cause one to try to charge another, and
around we go, a circulating current between the batteries that
will run them both down. And we don't even get to use the
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
PayPal ID "MotDog@..."