How far can you tip a golf cart battery before it spills?

[FreeLancer]

Before I go and learn the hard way, does anybody have any idea what the maximum operating angle these flooded lead-acid batteries were designed to be used at, without spilling?  I'm curious if I can save money over an AGM battery for a mobile backup power project I have in mind.

[lochaber]

Well I can tell you that I've seen people flip golf cars and the batteries still worked if that helps.

[FreeLancer]

Obviously, these batteries must be designed to handle some degree of movement from upright, but 90 degrees or more seems like a stretch.  I'm just wondering about tilting them 30 - 60 degrees for short distances around the house or in/out of vehicles, but I don't want to risk spilled acid ruining the container, cabling, fuses, and inverter, not to mention my investment in time.

[Nodularguy]

You cannot substitute a flooded lead acid battery for an AGM by tipping it on its side or at an extreme angle. The plates in a flooded lead acid battery are designed to be immersed in the electrolyte to function. By tipping the battery you will cause a portion of the plates to dry out and thus you will have reduced capacity and failure. Remember there is no electricity in a battery, the power comes from the chemical reaction of the acid mixture interacting with the entire plate structure. An AGM battery has a gel type electrolyte that works independent of position and gravity. It is also designed to be a sealed product and also must be charged at a different rate than a standard lead acid battery. Lead acid is designed to be in a vertical position to function.

[FreeLancer]

I'm not planning on buying a couple of golf cart batteries and operating/storing them on their sides, at 90 degrees from their normal upright position.  I know they're not designed for this, and I will deserve any mess that I have to clean up if I use them in this position.  Using an AGM or other sealed cell is the only sensible solution in this type of situation.

My question is how many degrees can golf cart batteries be tilted with a reasonable expectation that the caps will prevent any electrolyte spill?  Obviously these batteries are used to power moving vehicles, which are designed to climb and traverse slopes as part of their normal operation, so they must be engineered with some degree of tilt in mind.  My question is, what's a reasonable angle that a golf car would be expected to operate at without spilling electrolyte out of its flooded battery bank?

[Nodularguy]

I am a dealer for both Deka and US battery brand batteries. I could find nothing regarding angle of tilt operation. All I can do is offer some general battery advice. When a battery is discharged the electrolyte will be at its lowest level. You could tilt a battery in this state and measure using a protractor the angle at which the electrolyte stops covering the plates. The most important thing is to maintain coverage of the plates in electrolyte so they can function. On an automotive battery the venting is controlled a bit different than a deep cycle golf cart style battery. Deep cycle batteries use removable vent caps so you can add water to the battery. These caps do not seal the battery as venting must occur during charging of all lead acid batteries. They have tiny orifices that allow gas to escape during charging. Tilt it on it's side and electrolyte will leak out. An Automotive battery has tiny vents that are usually at each end of the case rather than on top, it will also leak if tipped. I have golf carts and have climbed some pretty steep hills, that made parts of me pucker up, without the electrolyte leaking out.  I did some playing around with my battery stock using a US BATTERY US2200XC which has a opaque case and you can see the electrolyte through it with a flash light. By tilting the battery on the long and short dimensions and measuring with a builders square I estimate the battery reached almost 35 degrees before the plates were uncovered. Due to gravitational force and design intent I would not recommend operating it at any angle but for short periods like climbing a hill. I have several golf carts, I am also a club car/Taylor-Dunn dealer. My Golf carts are also wired into my back up power grid and charge via my windmills. The batteries are tapped to to operate as normal for the golf cart, but also to attach to system to be the battery bank to feed the inverters in a power outage. I have emailed both East Penn and US Battery engineering department today to see if I can get a technical spec for you. My guess is there will be a legal mumbo jumbo response to cover their posterior, but thought I would try for you. Hope my mini-novel here has value for you.

[FreeLancer]

+1 Nodularguy, now we're getting somewhere!

I don't plan on discharging them in a tilted position, so keeping the plates covered isn't as critical to me as keeping the electrolyte from spilling out the caps.  The batteries would be in the bottom of a two-wheeled container that could be moved short distances, hand truck style.  It sounds like a 30 degree angle doesn't pose much risk, but I'd prefer 45 to 60.

[Nodularguy]

You will be fine if your not planning on operating them in a tilted position, just moving them around. We stack them three or four high on a hand cart and move them that way. If you were really concerned, they make shipping plugs that replace the vent caps and truly seal the battery. You could install them, move the batteries and then put the vent caps back on for normal operation.

[FreeLancer]

Do you think the regular vent caps can handle 45 degrees for a short-trip around the house?