I have a customer who needs a battery-powered system that will operate in any orientation. A car battery is the only thing that has the A-hrs he needs (I think). I assume a sealed car battery solves the obvious problem of leaking acid, but are there any other considerations that prevent a car battery from being used when it is upside-down? Are there other types of rechargeable batteries I should consider that give the same A-hrs (approx 240 A-hrs) as a car battery? ----------------------------------------------------------------- Dave Van den Bout / XESS Corp. (919) 363-4695 devb@xess.com
Can car batteries work upside-down?
Started by ●June 5, 2008
Reply by ●June 5, 20082008-06-05
On Jun 5, 10:24=EF=BF=BDam, Dave Vanden Bout <d...@xess.com> wrote:> I have a customer who needs a battery-powered system that will operate > in any orientation. =EF=BF=BDA car battery is the only thing that has the =A-hrs> he needs (I think). =EF=BF=BDI assume a sealed car battery solves the obvi=ous> problem of leaking acid, but are there any other considerations that > prevent a car battery from being used when it is upside-down? > > Are there other types of rechargeable batteries I should consider that > give the same A-hrs (approx 240 A-hrs) as a car battery? > > ----------------------------------------------------------------- > Dave Van den Bout / XESS Corp. > (919) 363-4695 > d...@xess.comRecharging issues might come into play with the battery in an other than upright position. I would check with some of the major manufacturers of Lead-Acid paste type batteries. Yausa, Panasonic, Exide, Eagle-Pichard, etc... In other words, a Google search. Unless we have a battery engineer here? Good luck. -mpm
Reply by ●June 5, 20082008-06-05
Dave Vanden Bout wrote:> I have a customer who needs a battery-powered system that will operate > in any orientation. A car battery is the only thing that has the A-hrs > he needs (I think). I assume a sealed car battery solves the obvious > problem of leaking acid, but are there any other considerations that > prevent a car battery from being used when it is upside-down? > > Are there other types of rechargeable batteries I should consider that > give the same A-hrs (approx 240 A-hrs) as a car battery? >I know for a fact that not all car batteries without visible fill holes are really sealed, and I wouldn't be surprised if none are. Even if they're "sealed" that usually means "sealed until it vents" (i.e. they have pressure relief valves), and the valve is going to be oriented down at some point in its life. I'd check the usual suppliers of _real_ sealed lead-acid cells and see if you can come up with a battery (or parallel combination thereof) that gets you sufficient capacity. I assume that your application is too cost-conscious to use Li-Po or NiMH? -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Do you need to implement control loops in software? "Applied Control Theory for Embedded Systems" gives you just what it says. See details at http://www.wescottdesign.com/actfes/actfes.html
Reply by ●June 5, 20082008-06-05
Dave Vanden Bout wrote: > Are there other types of rechargeable batteries I should consider that> give the same A-hrs (approx 240 A-hrs) as a car battery?Aircraft batteries might, although they will be expensive.
Reply by ●June 5, 20082008-06-05
"Dave Vanden Bout"> >I have a customer who needs a battery-powered system that will operate in >any orientation. A car battery is the only thing that has the A-hrs he >needs (I think). I assume a sealed car battery solves the obvious problem >of leaking acid, but are there any other considerations that prevent a car >battery from being used when it is upside-down?** No problemo........... Just put the car battery in a spinning centrifuge - so it always has it own positive gravity. ..... Phil
Reply by ●June 5, 20082008-06-05
Phil Allison wrote:> > ** No problemo........... > > Just put the car battery in a spinning centrifuge - so it always has it own > positive gravity. >Nice idea, came up with similar :-) Now propose how you'd make the necessary heavy duty connections to it :-p -- Adrian C
Reply by ●June 5, 20082008-06-05
On Thu, 05 Jun 2008 10:24:02 -0400, Dave Vanden Bout <devb@xess.com> wrote:>I have a customer who needs a battery-powered system that will operate >in any orientation. A car battery is the only thing that has the A-hrs >he needs (I think). I assume a sealed car battery solves the obvious >problem of leaking acid, but are there any other considerations that >prevent a car battery from being used when it is upside-down? > >Are there other types of rechargeable batteries I should consider that >give the same A-hrs (approx 240 A-hrs) as a car battery? > >----------------------------------------------------------------- >Dave Van den Bout / XESS Corp. >(919) 363-4695 >devb@xess.comPretty sure the gel-cell types can work in any orientation - Yuasa, Sonnenschein(sp?) etc. At least they have data sheets that will specify any orientation restrictions. They are available in similar sizes to car batteries.
Reply by ●June 5, 20082008-06-05
Tim Wescott wrote:> Dave Vanden Bout wrote: >> I have a customer who needs a battery-powered system that will operate >> in any orientation. A car battery is the only thing that has the >> A-hrs he needs (I think). I assume a sealed car battery solves the >> obvious problem of leaking acid, but are there any other >> considerations that prevent a car battery from being used when it is >> upside-down? >> >> Are there other types of rechargeable batteries I should consider that >> give the same A-hrs (approx 240 A-hrs) as a car battery? >> > I know for a fact that not all car batteries without visible fill holes > are really sealed, and I wouldn't be surprised if none are. Even if > they're "sealed" that usually means "sealed until it vents" (i.e. they > have pressure relief valves), and the valve is going to be oriented down > at some point in its life.Thanks for that information.> > I'd check the usual suppliers of _real_ sealed lead-acid cells and see > if you can come up with a battery (or parallel combination thereof) that > gets you sufficient capacity. > > I assume that your application is too cost-conscious to use Li-Po or NiMH? >Not really. I'm just trying to get the simplest system. A car battery is a single unit, they can easily buy several, and they can easily get a charger to recharge one while the other is powering their system for the day. I'm not averse to using Li-Po or NiMH batteries except that I don't want to build some custom enclosure to combine multiple cells to get the desired capacity, and I don't want to build some custom charger for it. Maybe these things are already commercially available, but I haven't looked. Others have mentioned lead-paste cells and aircraft batteries. Those are worth a look as well if a car battery won't work. Thanks to all who have replied. More replies are welcome! -- Dave Van den Bout / XESS Corp. (919) 363-4695 devb@xess.com
Reply by ●June 5, 20082008-06-05
Dave Vanden Bout wrote:> I have a customer who needs a battery-powered system that will operate > in any orientation. A car battery is the only thing that has the A-hrs > he needs (I think). I assume a sealed car battery solves the obvious > problem of leaking acid, but are there any other considerations that > prevent a car battery from being used when it is upside-down? > > Are there other types of rechargeable batteries I should consider that > give the same A-hrs (approx 240 A-hrs) as a car battery? > > ----------------------------------------------------------------- > Dave Van den Bout / XESS Corp. > (919) 363-4695 > devb@xess.comCar batteries don't like repeated deep discharge. For that, you need an RV/electric outboard battery. Dunno how sealed those are. Cheers, Phil Hobbs
Reply by ●June 5, 20082008-06-05
On Jun 5, 8:40 am, Dave Vanden Bout <d...@xess.com> wrote:> Tim Wescott wrote: > > Dave Vanden Bout wrote: > >> I have a customer who needs a battery-powered system that will operate > >> in any orientation. A car battery is the only thing that has the > >> A-hrs he needs (I think). I assume a sealed car battery solves the > >> obvious problem of leaking acid, but are there any other > >> considerations that prevent a car battery from being used when it is > >> upside-down? > > >> Are there other types of rechargeable batteries I should consider that > >> give the same A-hrs (approx 240 A-hrs) as a car battery? > > > I know for a fact that not all car batteries without visible fill holes > > are really sealed, and I wouldn't be surprised if none are. Even if > > they're "sealed" that usually means "sealed until it vents" (i.e. they > > have pressure relief valves), and the valve is going to be oriented down > > at some point in its life. > > Thanks for that information. > > > > > I'd check the usual suppliers of _real_ sealed lead-acid cells and see > > if you can come up with a battery (or parallel combination thereof) that > > gets you sufficient capacity. > > > I assume that your application is too cost-conscious to use Li-Po or NiMH? > > Not really. I'm just trying to get the simplest system. A car battery > is a single unit, they can easily buy several, and they can easily get a > charger to recharge one while the other is powering their system for the > day. > > I'm not averse to using Li-Po or NiMH batteries except that I don't want > to build some custom enclosure to combine multiple cells to get the > desired capacity, and I don't want to build some custom charger for it. > Maybe these things are already commercially available, but I haven't > looked. > > Others have mentioned lead-paste cells and aircraft batteries. Those > are worth a look as well if a car battery won't work. > > Thanks to all who have replied. More replies are welcome! > > -- > Dave Van den Bout / XESS Corp. > (919) 363-4695 > d...@xess.com<http://www.optimabatteries.com/optima_products/yellowtop.php> Mounts in "almost any position". G.