2V batteries with 4 bolt connetion between batteries - how to connect the cabel?

[Roil]

Hei

I am building a battery pack with 2V AGM 1000Ah batteries. They have a 4 bolt system. Not sure of the correct terminology - is this a 4 bus bar system?

I have got the batteries connected together but wonder how to connect the cables? Do I connect the cable directly to one of the four post or do I make a separate copper bar connecting the four cables "sticking" out and connect the cable to that?


DSC_0357.jpg

[Sunking]

Well what you have there is fork lift batteries and you are going to have to fabricate some term bars out of copper and plexiglass, fiberglass, or some other non conductive material. Those terminals supplied are engineered to connect directly to a fork lift speed controller.

[Mike90250]

Wow ! It's hard to see in your photo, but I assume there are 2 + wires and 2 - wires coming out of the side of your battery box? Will those cables flex enough and do they have a surface, that you can sandwich a copper bar between them and then a thru bolt for all 3 things ?

then I'd connect a fuse and then the battery cables to the short copper bar (that is not present yet) to get the wires someplace useful.

What is the voltage and amps of the battery bank??

What is it going to power, and what recharges it ?

[Roil]

Well what you have there is fork lift batteries and you are going to have to fabricate some term bars out of copper and plexiglass, fiberglass, or some other non conductive material. Those terminals supplied are engineered to connect directly to a fork lift speed controller.

The black connectors could well be from a fork lift system. The batteries however is not, they are standard deepcycle AGM batteries. Here is a picture of the battery top.

Suntek.JPG

[Roil]

Wow ! It's hard to see in your photo, but I assume there are 2 + wires and 2 - wires coming out of the side of your battery box? Will those cables flex enough and do they have a surface, that you can sandwich a copper bar between them and then a thru bolt for all 3 things ?

then I'd connect a fuse and then the battery cables to the short copper bar (that is not present yet) to get the wires someplace useful.

Hi Mike

The four in the picture is actually all (-) on the other side of the box it's four similar (+) cables.

Yes they are flexible enough to be bolted 2 and 2 together, I would have to shred some of the isolation away but thats doable. I just thought since they are all (-)'s and (+)'s why not bolt then directly onto a copper bar.

What is it going to power, and what recharges it ?

The Batteries are 2V 1000Ah and I got 12 of them. They are connected in 2 strings of 6 to make up a 12V system - 800kg (1600 pounds) of massive weight!
(YES I Know - it should have been 24V but I can't scrap my Victron inverter jet). So - it will be a 2000Ah 12V battery pack consisting of 2 strings of 6 of these batteries.

They will power my off grid cabin and are charge with 120A from the inverter whenever the generator runs, and from my 550W solar panels (and yes I know that it's very much in the low end, but the batteries has low resistance in particular in our cold climate. In addition I have a second supplementary charger with a 140A alternator with an advance 3 stage regulator.

[Sunking]

The batteries however is not, they are standard deepcycle AGM batteries.

Not so sure they are deep cycle then now that you shown the tops of one. What is the make and model number?

Those look like Station Batteries for a telecom or cell site. Something like this:



They are not made for cable interconnects. They are made for buss bars and Term Plates like you see above.

[SunEagle]

Not so sure they are deep cycle then now that you shown the tops of one. What is the make and model number?

Those look like Station Batteries for a telecom or cell site. Something like this:



They are not made for cable interconnects. They are made for buss bars and Term Plates like you see above.

Nice. Are those 12 batteries 2 or 4 volt?

[Sunking]

Nice. Are those 12 batteries 2 or 4 volt?

12 2 volt 1600 AH batteries at a Cell Tower Site or in other words 24 volts @ 1600 AH. What you cannot see in the pic is the 24 volt 1000 AMP rectifier and radio equipment they power.

[SunEagle]

12 2 volt 1600 AH batteries at a Cell Tower Site or in other words 24 volts @ 1600 AH. What you cannot see in the pic is the 24 volt 1000 AMP rectifier and radio equipment they power.

I would presume there is a firewall in between the two rooms.

[Sunking]

I would presume there is a firewall in between the two rooms.

Two rooms? No Sir a typical Cell Site building is 10 x 12. The recitifiers are lees than 4 feet from the batteries. They are just off camera right. In fact we mostly install the Rectifier Equipment Rack right on top of the battery stack to conserve space. This building is unique as it has a lot of equipment in it and is a larger building of 15 x 35, and since it has a 1000 amp recifier makes it too large to fit on top of the battery stack.

To take one step further in in large telephone offices and data centers the rectifiers are always installed as close as possible. It is done for two reasons:

1. Is to enable to keep voltage losses very low and to do that means keeping distances short.
2. Is related to #1 is economics. Get the batteries any distance away and you will go broke using much larger battery cables over long distances, not to mention one heck of a support issue with all that weight in copper laying up on cable racks..

Think of it this way. A 2000 AH battery typically uses 4 750 MCM copper cables to connect them to the charge buss. Two for pos, 2 for neg. 750 MCM cost about $20 per foot, and weighs 3 pounds per foot. Adds up real quick.

[inetdog]

This building is unique as it has a lot of equipment in it and is a larger building of 15 x 35, and since it has a 1000 amp recifier makes it too large to fit on top of the battery stack.

I am curious: The 1000A rectifier is sized to provide fast recharge when the power comes back after a loss, whether it was just the switchover to the generators or a complete AC failure.
But what is the range of the normal DC load that the battery/rectifier bank needs to support in a situation like that?

[Roil]

Gents - let's see if we can get this tread back on track

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Not so sure they are deep cycle then now that you shown the tops of one. What is the make and model number?

They are marked SUNTEK, model FL21000, not really sure about origin(probably "fare east"), I have bought them second hand.

They are not made for cable interconnects. They are made for buss bars and Term Plates like you see above.

Agree - indeed they are, these black connectors has an unknown origin. The batteries has been installed on a shut down Norwegian oil platform as power supply. My assumption is that oil industry regulation demanded insulated connectors and that buss bars where not allowed.


Sorry for the Norwegian language in the pictures .- I guess the graphs are understandable anyway.

You tell me what they are, and if they can last as energy storage for an off grid cabin with max 50 cycles of 50% SOC and 300 cycles of 1-2% per year


Type.JPG

[Roil]

And so back to the original question:

When you have a battery with more than one set of + / - posts, how do you connect the battery to the load?

[Sunking]

marked SUNTEK, model FL21000, not really sure about origin(probably "fare east"),

Sorry for the Norwegian language in the pictures .- I guess the graphs are understandable anyway.

Well I can figure out some, but not all.

Can you translate?

[SunEagle]

And so back to the original question:

When you have a battery with more than one set of + / - posts, how do you connect the battery to the load?

There must be some type of device that allows you to connect the 4 (+) or (-) flexible connectors to a common buss as well as have a place to connect cables to run to your load.

Seems like the battery manufacturer would also provide that type of buss connector since it includes the flexible connectors between the batteries.

Look at the pictures of Sunking's battery system. Those batteries have sets of 3 (+) and (-) terminals connected together by buss bars. The final connections go to terminals in a box that then connects to the load cables.