how do you check batteries (in a battery bank) to see if they are good?

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Giggles

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Hi, 

I bought an old FBI surveillance van, and hit has a LOT of batteries hidden in the bulkhead. There area at least 6- maybe 8, I have to take off the bulkhead cover to get aa better look at them, but I can see the + and - caps through a peek hole they built in the bulkhead. 

I'm going to take it into a guy who works on RV electrical systems, but he can't get my van in until January. So I'm wondering if anyone can tell me what kind of battery tester I need to get to check them myself.

If the are all dead, I might just strip the entire electrical system and start all over, because it is very, very VERY complicated, The guy who wired this thing up labeled everything in a very detailed manner, but it's Greek to me, because I know nothing about auto electrical systems (let alone complicated FBI electrical systems), except how to change a fuse and how to jump-start a dead battery under the hood. Lol.

I don't even know if the batteries in the batty bank are lithium, or lead, or AGM batteries yet, until I get the bulkhead off. Are there different battery testers for each kind of battery? Or, will one type of battery tester work on all of them?

Thanks
 
Take them out and take them to a Batteries+ store or a local shop that specializes in batteries to see about having them tested. They will have to be identified and charged as well as rested before they can be tested properly. It is a lot to be understood by someone that has never done it. It probably will be one of those drop them off and we will call you deals. It most likely will require an expensive charger and a tester with an experienced person to get an accurate test. There is a lot of information out there but there is a lot to understand plus safety concerns.
 
can you post some pictures of the batteries so we can see what you are dealing with. that way we can give you some pointers. you really need to learn electrical basics and checking your batteries certainly falls under that category.

lesson one,
AGM batteries are lead acid batteries it's the electrolyte that is in a different state. there are several types of lead acid batteries and they all have different charging rates.

highdesertranger
 
highdesertranger said:
can you post some pictures of the batteries so we can see what you are dealing with.  that way we can give you some pointers.  you really need to learn electrical basics and checking your batteries certainly falls under that category.

lesson one,
AGM batteries are lead acid batteries it's the electrolyte that is in a different state.  there are several types of lead acid batteries and they all have different charging rates.

highdesertranger

I know...I'm learning. Slowly but surely, I'm watching videos and learning.

I would take photos of the batteries, but I can't because the FBI hid them in the bulkhead behind the driver/passenger seat, and I haven't figured out how to take apart the bulkhead. I swear, the van is put together like Fort Knox. Lol.

However, I can see the ends of the batteries, and I think there are at least 8 batteries hidden in there. They were powering all their electronics plus a full size A/C unit, which is way more power than I need. Whoever putl this system together at the FBI was a genius...there are so many pieces of tape labeling every single wire, etc... The only problem, he didn't leave the schematic for the next person who bought it... (me).

I have an appointment to take it into some RV guys after the new year. They're going to look at the electrical system. It's way much more complicated than I could ever possibly work on my own, so I'm thinking of just telling them that if they cant figure out how its works relatively quickly, to just take everything out so I can just start over. There is soooo much wiring hidden in the walls and coming out of the walls...it's crazy. And there are at least 5 extra switches on the car dashboard, and I have no idea what they do. I'm a little afraid one of them might be an ejector seat. Lol. (Just kidding....sort of.)

I'm working tomorrow, but I'm going to try to take off the front of the bulkhead off after work, and if I can, I'll try to get a photo of the batteries.  If I can't get the bulkhead wall off, I'll just let the RV guys figure it out.
 
abnorm said:
And why did you remove the video from the previous thread ?????

Because I was afraid someone might steal my van if they knew what was inside.
 
Take a picture of what you can see, we may be able to tell from that.
 
It sounds like a professional job that would have used high grade components. I would be hesitant to rip it all out unless you intent to totally strip the interior and start with bare walls, but if I did I would want everything kept. There could be some modifications to the vehicle wiring system that might cause it not to work or cause more problems if components from the remains of the existing system are removed.
 
I'm positive on the high grade components, being a FBI vehicle I'm sure it was a budget is no object build.
 
bullfrog said:
It sounds like a professional job that would have used high grade components. I would be hesitant to rip it all out unless you intent to totally strip the interior and start with bare walls, but if I did I would want everything kept. There could be some modifications to the vehicle wiring system that might cause it not to work or cause more problems if components from the remains of the existing system are removed.

Thanks for the warning, and I think you may be right about that. I still can't figure out how to turn on any of the lights ini the back of the van. I've also found microphones, and speakers, and hidden switches and a periscope....but I can't figure out whaat any of the switches do, or how to turn them on.

I have found a thick, 3 pronged electrical cord coming out of each side of the bulkhead, and I think they may have charged the batteries with a generator before they took off on a stakeout, or surveillance mission. I'm not an electrician...but that's my best guess so far.

I also found a cable full of wires that goes from the bulkhead, and into the floor of the van. I looked under the van and saw that the cable goes all the way to the back of the van, but I had no idea whaat it was attached to back there, because I don't know that much about cars. But the cable has been cut inside the van, and it's no longer attached to the battery bank. I want to take it out because I don't like having a cable full of open wires hanging out in the van while I'm driving it, but I need to find out what it's attached to under the van before I can remove it.

It's definitely going to be a fun project that will keep me busy this winter!
 
Ok I was able to take apart some of the bulkhead to expose tbe batteries, and I got photos. There are 4 very large batteries, two on each side of the bulkhead.

Here are some photos. Any ideas what kind they are?
 
Hmmm...having a hard time posting the.photis....let me try again....
 
Ok, I couldn't figure out how to post photos, so I made a video of them. Any ideas?

 
About the batteries, they have manufacturing date on them. If they are over 5-6 years old, you are better off getting new ones.
 

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