Fed up with batteries

[kastein]

I think you may be confused, dmetalmiki. If there is a disconnect anywhere, no current is flowing, though voltage may be present.

If you put a disconnect on either side of the battery, right at the battery, you will have no real danger. The issue that arises in a 24 volt or 24/12 volt hybrid system is that if you use a positive disconnect on just the 24 volt (positive of second battery) you will still have the potential for a fault or short anywhere on the 12 volt circuit! But if you disconnect the ground, only faults between the 12 and 24 volt positive circuits or possibly a fault on the 12 volt circuit can cause you trouble. Ideally, all but one circuit (i.e. ground and 12 volt, or 12 volt and 24 volt, or even ground and 24 volt) leading to the battery would be disconnected when the shutoff is active. Or even all 3, but that is not necessary.

You can view voltage as being the same as pressure in a water pipe, and current as flow. Resistance is about the same as a pressure regulator or metering orifice; inductance would be the resistance to change in flow, effectively mass flow (i.e. what causes water hammer.) Capacitance is the same as a storage tank. In this case you would have effectively a pump that increases pressure by say 24psi, it is fine if you disconnect and cap either its inlet or its outlet because it will either have nowhere to push the water to, or nowhere to pull it from.

 

[emr]

a good rule is to clean and charge all batts fully and let em sit for a day to lose surface charge and then do a hydrometer test, this is the only test that really really tells the story of each cell, if they the batts u are using do not match up do not put them in, follow this rule and U will never have this happen, but like said above, safety glasses at the least, at the very least charge em up individually and load test em , this is a good way to see if they are close watch the meter, do not ever use batts that do not mate up in there stage of life is the best way I can put it,

 

[dmetalmiki]

not confused lol

just tried to explain for everyone to understand. still applies current WILL flow if ya stick yer fingers in! (never said it flowed with wires cut/ circuit broken.. )just that (as you point out POTENTIAL is there.). and I match all my batteries now. whatever power. I actually have two huge 120 amp batteries under floor in the reo camper, and two 120 amp batteries in the batt compartment, (now the batt box is removed.) they can be switched in (joined) together for starting, or for running the 2500 wat inverter. Power needed for an oil pump which primes the engine oil/turbo system before hitting the start button.

 

[cranetruck]

There is a reason for disconnecting the ground (-) first when working on batteries; you can't accidentally short something to chassis.

You can't compare house current to a set of vehicular batteries. House current is referenced to earth ground...a little difficult to disconnect.

 

[stumps]

I am certain that most of the battery explosions described in this thread are the result of battery abuse. Lead acid batteries are delicate for being so heavy. They don't take well to vibration, dropping, and they really don't take well to having their terminal posts flexed when making, or breaking, battery connections.

When a lead acid battery is constructed, it is cast out of lead as a unit: battery posts, lead bus bars (inter cell connectors), and lead plates. When you tighten the terminal, or tug and pull on it to remove it from the battery post, you are tugging and pulling on the lead bus bar that connects to the lead plates on the end cells. The lead bar is quite strong, but the junction between the bar and the plates can break easily. When this breakage occurs, it reduces the capacity of the battery, and it makes an area where a spark could occur inside of the battery.

Clean your terminals and cable ends with the appropriate terminal brush, and when you make the connection, be gentle. There is no need to really crank down on battery terminals.. just a little beyond finger tight is fine for a properly fitted cable end. The nut and bolt head shouldn't be buried in the lead! When you remove the battery clamps from the battery post, spread the clamp first to release it. Be gentle! If you can see the terminal post flex and move when you are working on the battery terminals, you are damaging the battery.

Always make the last connection to the battery away from the battery. When jumping, or charging, a negative ground system, connect the "+" terminal first, and then connect the "-" lead to the engine ground. No sparks anywhere near the battery! Certainly no sparks above the battery where the lighter than air hydrogen goes.

-Chuck

 

[kastein]

^^ things like that are why I like brass battery terminals more than lead ones. They flex more without deforming, so they usually loosen up and come off of the posts easier than lead terminals do.

 

[Z71]

Never work with safety glasses at the least .

How about "never work without them?

 

[bearboley]

Batteries vent hydrogen gas, anyone heard of the Hindenberg?

 

[nmwildman013]

One more thing. Never, ever, charge or jump a discharged battery that has been sitting in below freezing weather. Batteries can freeze when discharged and they will blow up when frozen if you try to push a lot of current through them.... personal experience when I used to do service in Colorado.

 

[Darwin T]

i have two questions.

#1 - the 12 volt stuff you took off and moved, was it just hooked to one battery or to some sort of equalizer? if you were pulling from just one battery that would explain the unequal charge between the two.

#2 - how are you charging the 12 volt battery? if you are pulling from one battery on the 24 volt system then you will have the same problem.

i am working towards a wolverine tech 24 volt / 12 volt system for my M109a3. the regular 24 volt for the truck and a 12 volt altenator for the batteries for the inverter for the box. that way it is two seperate systems. however i do have a desulfator on my 24 volt system and a priority start system also. the priority start shuts down any drain before it can kill the battery and keeps enough power to start the vehicle. plus i use Optima Batteries because of the vibration issue.