The fit of a EPOCH 300 ah in the battery box

[BikeCamper]

Appreciate the update. Good to know about the warranty being voided by shaving the handles. That seems unreasonable to me, but nevertheless good to know. I guess I would make a slight mod to the battery box, then, to accommodate the handles.

[thiel]

Hey there... I have a 2016 trailer as well so our battery boxes are probably the same size.

You might take a look at Renogy's new "core mini" 100ah battery. I was able to easily fit three of them in my battery box. Plenty of height and space enough for a (yet to be installed) blue sea cutoff switch.

[JeffKim]

Originally Posted by thiel

Hey there... I have a 2016 trailer as well so our battery boxes are probably the same size.

You might take a look at Renogy's new "core mini" 100ah battery. I was able to easily fit three of them in my battery box. Plenty of height and space enough for a (yet to be installed) blue sea cutoff switch.

My, they have gotten a lot smaller.

Just wondering, it appears to me the batteries are not in balance. The battery with the postive cable coming in should be the last battery with a negative cable. And vice-versa the negative coming in should be the last in line for the postive cable.

[StogieMan]

Originally Posted by JeffKim

Looks great! I was wondering too about fusing. It looks like you retained the MRBF fuses? I kept ours for the inverter and batteries when I installed our 400Ah, but a lot of people use a Class-T.

Also, keeping the Victron shunt means you can use the VE.Smart Networking if you have a Victron Smart solar charger or add other Victron equipment in the future.

I’ve gone down the redundancy route and have added both. Each positive terminal has an MRBF fuse and I have a Class-T about 8” off the positive battery terminal.

Originally Posted by Bnystrom

While Class T fuses may be the best type for the application, they're expensive, can be hard to find, and most important for this installation, they're bulky. I don't see where he could actually fit one, or even an ANL fuse and holder.

This use to be case during COVID but now readily available. Victron now also makes a Lynx Class-T Power In that allows you to put two class-t fuses in them. However, for the OP it might be tough to add it as you want to have a class-t fuse as close as possible to the battery.

Lastly, the Epoch 460 Ah batteries come with a built in class-t fuse which is nice. A bit too big to fit for the OP though. It’s probably just a matter of time before Epoch probably starts installing them inside the 300 Ah batteries which will be nice and welcomed.

Now I have triple redundancy as our 460 Ah Epoch batteries have built in class-t fuses. Now we have an MRBF fuse on each positive battery terminal, a class-t fuse 8” from the closest battery positive terminal and one each class-t fuse in each battery. Hey - I can sleep better at night!

Victron Class-T Power In:

https://www.currentconnected.com/pro...iAAEgKBmfD_BwE

[thiel]

Originally Posted by JeffKim

Just wondering, it appears to me the batteries are not in balance. The battery with the postive cable coming in should be the last battery with a negative cable. And vice-versa the negative coming in should be the last in line for the postive cable.

Tell me more... I'm clueless about this level of detail...

[Bnystrom]

It's actually pretty simple, if you pull both cables off of one battery, that battery will take the bulk of he load and they others will take less. They won't charge evenly, either. This leads to battery imbalance.

With two batteries, pulling the positive lead off one and the negative lead off the other insures that they share the load and charge evenly.

When you add more batteries, this still works to an extent, but the middle battery (or batteries) takes less of the load and charge. At that point, the best solution is to use bus bars for both the positive and negative connections.

Run equal-length cables from each positive battery terminal to the positive bus bar. You can use your main battery fuse block as a bus bar and just run the three (or more) battery cables to one side.

You also need to run equal-length cables from each battery to the negative bus bar, but they don't have to be the same length as the positive cables. If you're using a chassis ground, you can run all three negative cables to the same ground point, if that's easier.

When I did our lithium conversion, I started with one 300Ah battery. When I added a second battery, it was simpler to go the bus bar with chassis ground route, but it wasn't strictly necessary. In the pic, you can see the positives going to the main battery fuse and the negatives to a chassis ground.

[Bnystrom]

[QUOTE=StogieMan;2762911]Now I have triple redundancy as our 460 Ah Epoch batteries have built in class-t fuses. Now we have an MRBF fuse on each positive battery terminal, a class-t fuse 8” from the closest battery positive terminal and one each class-t fuse in each battery. Hey - I can sleep better at night!QUOTE]
All this really does is add several unnecessary connections that increase resistance in the system and create more potential points of failure. Ask an electrician and they'll tell you the fewer connections, the better.

[BikeCamper]

All the cabling and balancing requirements for multiple batteries is one of the reasons I prefer a single-battery solution. Another is the increased possibility of a bad battery when multiple batteries are involved. Premature failure of one battery will usually necessitate swapping all batteries out, because it’s inadvisable to mix batteries of different ages.

[JeffKim]

Originally Posted by thiel

Tell me more... I'm clueless about this level of detail...

@Byn describes it well. Battery imbalance can be a big deal with lithium batteries. There's another thread (can't find it) where the poster ruined his Battleborns with an imbalanced topology (as they call it). One battery was being constantly drained and recharged while the others never received a balancing voltage (from what I gather).

Anyways, having positive and negative bus bars is ideal, but you can just rearrange your cables and get close enough to ideal. I labeled your batteries and you can move the negative cable coming in from #2 to #3. Then move the negative cable going from #3 to #1 to between #3 to #2 (hopefully it reaches). Leave the positives as they are.

With our 4x100Ah under the bed I couldn't get the cables to be equal length which is closer to ideal, but I'm not too worried since I don't think the wire resistance is that significant. And I have cheap batteries, so it's not as big of an investment. I expect batteries will get even smaller and maybe in a few years I can put 8x100Ah in the same space.

[bdavies]

On 7/23/24, I spoke with James at Epoch Batteries, and he told me that trimming a handle off the side of the battery would NOT affect the warranty, unless you caused some actual damage to the battery itself.

I used a hack-saw to easily cut just a bit off of one handle and that allowed the battery to easily fit into the box.

[BikeCamper]

Originally Posted by bdavies

On 7/23/24, I spoke with James at Epoch Batteries, and he told me that trimming a handle off the side of the battery would NOT affect the warranty, unless you caused some actual damage to the battery itself.

I used a hack-saw to easily cut just a bit off of one handle and that allowed the battery to easily fit into the box.

That seems much more reasonable/sensible. It is too bad the answer seems to depend on who happens to answer the phone.

[Bnystrom]

Originally Posted by BikeCamper

That seems much more reasonable/sensible. It is too bad the answer seems to depend on who happens to answer the phone.

Get it in writing! Even an email is enough.

[Bigboote]

Here is the spec sheet on the Epoch 12V 300Ah | Heated & Bluetooth | LiFePO4 Battery

My battery box on a 2024 27 is 15" x 13. It looks to me like the current battery will fit just fine.

Am I wrong?

https://cdn.shopify.com/s/files/1/02...f?v=1692809717

[F250]

Originally Posted by Bigboote

Here is the spec sheet on the Epoch 12V 300Ah | Heated & Bluetooth | LiFePO4 Battery

My battery box on a 2024 27 is 15" x 13. It looks to me like the current battery will fit just fine.

Am I wrong?

https://cdn.shopify.com/s/files/1/02...f?v=1692809717

That's what I thought, because I looked at the same spec sheet. But if you go to this other part of their website here:

https://www.epochbatteries.com/produ...och-essentials

And then go down to

Weights and Dimensions:

Weight: 58 (LBS)
DIMENSIONS
Length: 13.75" @ Base, 15.5" @ Handles (inches)
Width: 7.75 (inches)
Height: 10.5 (inches)

Note it will show the width of 15.5" where the handles are. The problem is that handles are part of the batteries body, and therefore they would have to be trimmed 1/2 inch if you want to put it into many of our battery boxes. I called Epoch and they told me that I would void my warranty if I trimmed the battery case, another member called too and they told them it wouldn't.

The spec sheet is very misleading because it is the measurement of the base versus widest part of the batteries at the built in molded handles.

[gypsydad]

Sorry the Epoch 300AH would not work for you. I just saw the LiTime 100AH Group 24 with Bluetooth are on sale $199/each. I paid $250~ each for these back in Aug. and we are very happy with making the switch from Lead Acid. Recently went 5 days without charging using lights and furnace, and still had 57% charge left.

https://www.litime.com/products/12v-...mart-bluetooth

[thiel]

Originally Posted by JeffKim

Anyways, having positive and negative bus bars is ideal, but you can just rearrange your cables and get close enough to ideal. I labeled your batteries and you can move the negative cable coming in from #2 to #3. Then move the negative cable going from #3 to #1 to between #3 to #2 (hopefully it reaches). Leave the positives as they are.

I'm not sure I fully understood your directions, but I gave it a go (and added a disconnect). How does this look to you?

[JeffKim]

Originally Posted by thiel

I'm not sure I fully understood your directions, but I gave it a go (and added a disconnect). How does this look to you?

Maybe I instructed you wrong, but not there yet. The negatives should go from #3 to #2 to #1. The positives from #1 to #2 to #3. So basically the last negative should end up at the battery where the positive comes in. And the last positive should be the battery where the negative comes in. So just switch the negative from #3-#1 to #3-#2.

[thiel]

Originally Posted by JeffKim

Maybe I instructed you wrong, but not there yet. The negatives should go from #3 to #2 to #1. The positives from #1 to #2 to #3. So basically the last negative should end up at the battery where the positive comes in. And the last positive should be the battery where the negative comes in. So just switch the negative from #3-#1 to #3-#2.

Ah... that makes sense (and I see now how that's what you told me the first time).

Any concerns/modifications I should make because of the two positive leads? Should they both be at one end of the array?

THANKS!

[Wazbro]

Originally Posted by thiel

Ah... that makes sense (and I see now how that's what you told me the first time).

Any concerns/modifications I should make because of the two positive leads? Should they both be at one end of the array?

THANKS!

Yes they should both be at the end.

[thiel]

Originally Posted by Wazbro

Yes they should both be at the end.

At one end? Or can they be one at each end, as is currently the case?