Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-24-2022, 02:00 PM   #1
2 Rivet Member
 
2021 25' Flying Cloud
Edgewater , Maryland
Join Date: Aug 2020
Posts: 24
Shunt vs Lithium w/BMS & Bluetooth

Hi All,

Was planning on adding a shunt as I transition to lithium. Met with Lion Enerty at Hershey RV show and heard they are coming out with bluetooth in their BMS.

Question - if I can get accurate SOC directly from each battery via bluetooth, are there other benefits to having a shunt?

Thanks,
Greg
Dr. Ohat is offline   Reply With Quote
Old 09-24-2022, 02:21 PM   #2
3 Rivet Member
 
2017 25' Flying Cloud
Raleigh , NC
Join Date: Jul 2017
Posts: 169
Consider where you are to place them, some of the batteries with shunts are not water resistant so should not be in an external battery box.
JoeHTP is offline   Reply With Quote
Old 09-24-2022, 03:04 PM   #3
Site Team
 
richard5933's Avatar

 
1994 25' Excella
Waukesha , Wisconsin
Join Date: Sep 2020
Posts: 4,131
Images: 4
If you have a Victron system with a touch screen, having the shunt means that the information will be displayed on the screen. Infinitely easier than having to do it on an app.

Even without the touch screen, I find being able to have both of us see the data on the smaller monitor instantly quite convenient. I'm the only one who will use an app to monitor something like this, so if I expect my other half to ever help keep an eye on things it better be right out there in the open. Besides that, there are times I don't feel like carrying the phone around or even going to find it, so glancing at the monitor is always an option.

Aside from all that, there are other things you can do with the Victron shunt, such as use it to open/close remote relays and activate other devices depending on various set points. Not sure if the BMS on the batteries can do that.
__________________
Richard
11018
1994 Excella 25 Follow the build on Gertie!
1999 Suburban LS 2500 w/7.4L V8
1974 GMC 4108a - Custom Coach Land Cruiser (Sold)
richard5933 is online now   Reply With Quote
Old 09-24-2022, 04:49 PM   #4
2 Rivet Member
 
Lucky Skunk's Avatar
 
Currently Looking...
Monterey , California
Join Date: Dec 2021
Posts: 52
We chose to not have the additional monitor inside and to exclusively use the app. I regret the decision!
Lucky Skunk is offline   Reply With Quote
Old 09-24-2022, 05:01 PM   #5
Half a Rivet Short
 
2017 30' Classic
2022 Interstate 24X
Carlisle , Pennsylvania
Join Date: May 2017
Posts: 14,861
Hi

The charge data that comes from a BMS is a bit suspect. Even the data from a proper shunt has it's limits. The better result will come from the external shunt.

Bob
uncle_bob is offline   Reply With Quote
Old 09-24-2022, 07:40 PM   #6
4 Rivet Member
 
1949 22' Liner
1969 27' Overlander
1969 27' Overlander
Walnut Creek , California
Join Date: Apr 2015
Posts: 323
I have been using the Renogy Smart Lithiums with a wired battery monitor that just plugs in. I also have the app on my phone with the Bluetooth info from the Solar and DC 2 DC chargers. It gives you all of the info you would ever need without a shunt. And it is all plug and play. Very simple to use. And that is good.
Jcondon is offline   Reply With Quote
Old 09-24-2022, 07:56 PM   #7
4 Rivet Member
 
1949 22' Liner
1969 27' Overlander
1969 27' Overlander
Walnut Creek , California
Join Date: Apr 2015
Posts: 323
Quote:
Originally Posted by uncle_bob View Post
Hi

The charge data that comes from a BMS is a bit suspect. Even the data from a proper shunt has it's limits. The better result will come from the external shunt.

Bob
The Smart BMS is way more accurate than a Smart shunt especially if your Peukert Exponent is off a bit. Calculating the SOC has way more possible errors than reading the SOC from the BMS.
Jcondon is offline   Reply With Quote
Old 09-24-2022, 07:58 PM   #8
4 Rivet Member
 
1949 22' Liner
1969 27' Overlander
1969 27' Overlander
Walnut Creek , California
Join Date: Apr 2015
Posts: 323
Quote:
Originally Posted by Dr. Ohat View Post
Hi All,

Was planning on adding a shunt as I transition to lithium. Met with Lion Enerty at Hershey RV show and heard they are coming out with bluetooth in their BMS.

Question - if I can get accurate SOC directly from each battery via bluetooth, are there other benefits to having a shunt?

Thanks,
Greg
No. The future is the Smart BMS. Here is the Victron Smart Shunt manual. Just realize you will not have to do any of this! https://www.victronenergy.com/upload...rtShunt-en.pdf
Jcondon is offline   Reply With Quote
Old 09-25-2022, 07:59 AM   #9
Half a Rivet Short
 
2017 30' Classic
2022 Interstate 24X
Carlisle , Pennsylvania
Join Date: May 2017
Posts: 14,861
Quote:
Originally Posted by Jcondon View Post
The Smart BMS is way more accurate than a Smart shunt especially if your Peukert Exponent is off a bit. Calculating the SOC has way more possible errors than reading the SOC from the BMS.
Hi

You are putting a lot of trust in folks who have come up with defective BMS implementations time after time after time ......

There are ton of threads on how to set things up correctly. The shunts work well. The BMS internals are very much an unknown.

Bob
uncle_bob is offline   Reply With Quote
Old 09-25-2022, 10:39 AM   #10
3 Rivet Member
 
1985 31' Excella
st. Paul , mn
Join Date: May 2007
Posts: 214
1st iff the word shunt is a vari simple component that is in series with the negative side of a battery = the only function it to allow a sensor tap --- the end .
A BMS has this component on a circuit board with many other components .
If you get enough info [ that you want ] then your good .
If you want more info , data tracking , physical display - then you could add a BlueTooth display that mounts to where you need it .
This is a shunt Google search says a little over $22 for 50 amps .
Depending on your abilities , you use the BT in the BMS , add a shunt [ rated for max current of system ] and any kind of metering - to me a meter that records input & output of system .

Buying from a single brand allows extreme lack of knowledge & ability , but at typically very high prices .
I prefer to know enough to reduce costs & repair when issues come up .

All above is just a matter of choice
__________________
85 Excella , 31' , electric brakes , R. twin [ would like it to be a single ] , future upgrades , composting toilet [ replace black water tank with a 2nd fresh ] , solar power , instant hot water heater .
Tow 94 Dodge Ram , 4x4 , Cummins , AT .
JohnTF is offline   Reply With Quote
Old 09-25-2022, 06:05 PM   #11
2 Rivet Member
 
2021 25' Flying Cloud
Edgewater , Maryland
Join Date: Aug 2020
Posts: 24
Thanks all for the various perspectives. I guess I can try the BMS w/BT and see how it works and always add the shunt later. My first priority is getting the additional power from the Li batteries.

Thx,
Greg
Dr. Ohat is offline   Reply With Quote
Old 09-26-2022, 04:29 PM   #12
3 Rivet Member
 
Bacliff , TX
Join Date: Dec 2019
Posts: 146
The external monitors such as the Victron 712 or SmartShunt provide better data. It seems that as good of an idea as the internal monitors are - they are not all that reliable.
jimdelane is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Victron Smart Shunt Install Confirmation for Next Step Lithium Upgrade Electronut Batteries, Univolts, Converters & Inverters 20 07-01-2022 11:24 AM
Use of PI 30A bms in 50A plug kmrice Batteries, Univolts, Converters & Inverters 1 03-15-2021 03:47 PM
wiring Housepower BMS momentary switch northfielder Airstream Motorhome Forums 0 01-14-2017 11:53 AM
TriMetric 2020/2021 shunt - 100 or 500 amp? ostream Electrical - Systems, Generators, Batteries & Solar 3 11-06-2008 03:37 PM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 01:47 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.