Feedback on a Camper Van Setup

[extraj]

I bought a camper van with a partial setup, and am getting ready to assemble an upgraded system with a new lithium phosphate battery bank. I'm relatively new at this, and would love to get some feedback on this setup.

I already had a lot of the parts, so it's not as elegant as it could be, but I think it should suit my needs.

Here's a link to the draw.io file, a jpg is attached.

 

[svetz]

I'm not familiar with Chargery, do the power leads not connect to it?

 

[HaldorEE]

I am not familiar with the Chargery BMS either. It may be a fine choice, but it may be more complicated to use than you really want to deal with.

Another option you might want to consider is the 4S, 100A BMS with low temperature cutoff that Battery Hookup sells. It is not configurable, but as long as it is comes set correctly that could actually be a good thing.

Li-ion/Lifepo4 3s-20s 100a BMS W/ LOW TEMP CUTOFF

--------------------Here are 100a BMS units. We carry 3s-20s and both Lithium Ion (Li-Ion) and Lithium Iron Phosphate (Lifepo4). The lithium ion version also works with Lithium Polymer (Li-Po) since they both have the same parameters. (WIRING DIAGRAM BELOW!) Some of the BMSs arrived without the...

batteryhookup.com

100A should be big enough for a 1500W inverter.

-Edit-

If you need more than 100A, things get a bit more dicey. The Daly BMS comes in a 150A version, but lacks cold temperature charge cutoff. I believe the Chargery does have cold temperature cutoff, but I am not at all familiar with them beyond having heard the brand name.

The Victron BMV-712 battery monitor can provide a low temperature charge cutoff via Bluetooth to Victron SmartSolar Chargers. The BMV-712 also has a relay output you could use to disable the other charge sources when the battery temperature is too low (assuming they can accept that).

 

[HaldorEE]

I also don't see a circuit breaker or fuse in the battery input. I would replace your battery switch with a 150A circuit breaker. You can still use it to disconnect the battery and if something shorts out, you won't set fire to your RV. Something like this:

Blue Sea Systems 7189 Surface Mount 285-Series Circuit Breaker 150 Amp

 

[HaldorEE]

This version is 120A which is definitely enough for your Inverter. Has communication too (Bluetooth) which is nice.

4S or 3S 12V Li ion or Lifepo4 Battery smart BMS with Bluetooth function UART and RS485 communication with 60A to 120A constant current – LLT POWER ELECTRONIC

 

[HaldorEE]

Here is a thread that discusses these alternative BMS in detail (58 pages!)

Finally found a LiFePO4 BMS with Low-temp Charging Protection

Spent the last few days and tonight testing BMS: 1. The "new" daly LiFePO4 BMS (that states in the data sheet that it has low temp charging protection) does not have low temp charging protection. And yes, it has a temp sensor attached. This disappointed me big time. Video to come. 2. Next, I...

diysolarforum.com

 

[extraj]

Thanks for all the responses, everyone!

I'm not familiar with Chargery, do the power leads not connect to it?

The BMS connects directly to each cell for monitoring and balancing, but the main power leads connect to the DCC, which the BMS controls.

https://chargery.com/doc/Chargery_BMS8T_specification_V4.1.pdf

I am not familiar with the Chargery BMS either. It may be a fine choice, but it may be more complicated to use than you really want to deal with.

Another option you might want to consider is the 4S, 100A BMS with low temperature cutoff that Battery Hookup sells. It is not configurable, but as long as it is comes set correctly that could actually be a good thing.

Thank you! I already have the Chargery kit, so am going to move forward with that for now. I would have gone with something like the Overkill Solar BMS, but wanted a little more headroom in case I need to pull more amps in the future.

I also don't see a circuit breaker or fuse in the battery input. I would replace your battery switch with a 150A circuit breaker. You can still use it to disconnect the battery and if something shorts out, you won't set fire to your RV. Something like this:

Blue Sea Systems 7189 Surface Mount 285-Series Circuit Breaker 150 Amp

Thanks! That makes sense and I'll do that.

 

[svetz]

Just a word of caution when sizing wires, a lot of recent posts haven't been considering wire ampacity. Don't be that guy! ?
This calculator has a warning if it exceeds ampacity.

 

[extraj]

Just a word of caution when sizing wires, a lot of recent posts haven't been considering wire ampacity. Don't be that guy! ?
This calculator has a warning if it exceeds ampacity.

Thank you! Yes, have a spreadsheet of amperage, wire length, and gauge. My better half is alarmed by how much I've spent on wiring.

 

[extraj]

I have a heat shrink crimper for everything up to 10AWG, but haven't figured out how I'm gonna crimp the big ones yet... Hoping to find a friend with a nice hydraulic crimper to lend.

 

[Hedges]

I have a heat shrink crimper for everything up to 10AWG, but haven't figured out how I'm gonna crimp the big ones yet... Hoping to find a friend with a nice hydraulic crimper to lend.

You can buy some ready-made cables with ring terminals crimped on, eBay etc. Cut in half if other end goes to a lug.

I bought ready-made 4/0 cables to go between my batteries. Also MC cables I cut in half for pigtails to connect PV panels. I had a cheap hydraulic crimper up to 2/0 so I did those for battery to each inverter.

 

[HaldorEE]

You can buy some ready-made cables with ring terminals crimped on, eBay etc. Cut in half if other end goes to a lug.

I bought ready-made 4/0 cables to go between my batteries. Also MC cables I cut in half for pigtails to connect PV panels. I had a cheap hydraulic crimper up to 2/0 so I did those for battery to each inverter.

These guys will custom make cables for you at whatever length you want with whatever termination you need.

Quality Copper Battery Cables Made in the USA! - BatteryCablesUSA

www.batterycablesusa.com

I bought a set of these for my 24V battery pack. I am in Phoenix and wanted to be able to remove the battery from the RV when it is not in use (so I can keep it cool during the summer).

Anderson SB175 Copper Battery Cable Assembly 1/0 Gauge AWG w lug/terminal/clamp

www.batterycablesusa.com