Advice on DIY lithium configurations for Jimny!





Page 1 of 2 1 2 LastLast
Results 1 to 20 of 32
  1. #1
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Question Can I connect LiFePO4 prismatic cells side by side?

    Can any guru’s advise on the following:

    1. Can I connect the cells side by side on the short edge to make a long flat 12v battery?
    This would be fastened to a thin piece of wood or alu with vent holes drilled out, and bolted to the floor. Rough diagram below (as viewed from the top, this would be flat, below the baseboard)

    Click image for larger version. 

Name:	52644F54-698E-4876-993C-E39DE8BC2A85.jpg 
Views:	156 
Size:	27.3 KB 
ID:	589471

    2. The BMS.
    The Daly bms that comes with the kit doesn’t seem to have over&under temperature protection. It does have “working temp -20 to 70”

    - is working temp the same as protection and are those cutoffs fine for lifepo4?
    - is temp protection important to have?
    - should I opt for different bms, what would you recommend?

    See bms specs below from supplier:


    Click image for larger version. 

Name:	81E2B8BC-8B8B-422E-94D2-9926BC333D79.jpg 
Views:	138 
Size:	34.8 KB 
ID:	589472
    Click image for larger version. 

Name:	58E5E639-03F6-4031-88D8-62C9A52ADAC2.jpeg 
Views:	106 
Size:	100.8 KB 
ID:	589473


    The above 120ah battery would (at this stage) ideally be paired with a Victron batter monitor (712) and a WRND dcdc.

    The reason for the questions is that I am planning a new aux battery (lifepo4) DIY install in our Jimny...which is TINY so we need to maximise space and keeping a battery box in the cab is quite big. I have removed the rear seats and added added a baseboard, and noticed I have a bit of unused space to work with. A flat wide battery bank would sit in here perfectly. Setup does not need to be portable.

    Please let me know what you think, what you would change and what else you would or consider?

    Thanks in advance!!!
    Last edited by jonnyr; 2020/09/21 at 03:24 PM. Reason: Table didn’t show up, so added screenshots incase.
    Suzuki Jimny (2015)



  2. #2
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    [EDIT]

    The manufacturer has responded, saying that yes indeed, one can connect them side by side.

    My remaining question is regarding the necessity of a BMS with low temperature cut-off, and your thoughts and advice on the system + components / chargers / monitors.

    Thanks!
    Suzuki Jimny (2015)



  3. #3
    Join Date
    Nov 2008
    Location
    Ellisras
    Age
    57
    Posts
    1,165
    Thanked: 859

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by jonnyr View Post
    [EDIT]

    The manufacturer has responded, saying that yes indeed, one can connect them side by side.

    My remaining question is regarding the necessity of a BMS with low temperature cut-off, and your thoughts and advice on the system + components / chargers / monitors.

    Thanks!
    You might have to be careful where you plan to mount/install the BMS - the 4S BMS do not have very long cell monitoring wires.
    (I suppose one can lengthen them but I would not fiddle it)
    Rudolf Ras
    Don’t blame yourself over past mistakes. It’s like driving down the N1 while looking in the rear view mirror only.

    2000 Patrol GU 4.2D(onkey) "old-timer" and wise at 853 000 km
    2014 Patrol GU 3.0CRD "teenager" in puberty at 117 000 km
    2007 Echo3 Trailer "the nest" Braked Axle fitted at +60 000 km
    2012 NP300 YD2.5 D/C 2x4 High Rider "platkar" at 124 000 km

  4. The Following User Says Thank You to Dungbeetle For This Useful Post:


  5. #4
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by Dungbeetle View Post
    You might have to be careful where you plan to mount/install the BMS - the 4S BMS do not have very long cell monitoring wires.
    (I suppose one can lengthen them but I would not fiddle it)

    Thanks @Dungbeetle. Yes true - good point, even the main terminal cables looks like it's pretty short. If it will work and this BMS is suitable, I think lengthening the cable might be what I need to do for this setup - Sub-question: best advice on how to join longer cables in if needed?
    Last edited by jonnyr; 2020/09/21 at 04:23 PM.
    Suzuki Jimny (2015)



  6. #5
    Join Date
    Nov 2015
    Location
    Cape Town
    Posts
    741
    Thanked: 927

    Default Re: Can I connect LiFePO4 prismatic cells side by side?

    Quote Originally Posted by jonnyr View Post
    Can any guru’s advise on the following:

    1. Can I connect the cells side by side on the short edge to make a long flat 12v battery?
    This would be fastened to a thin piece of wood or alu with vent holes drilled out, and bolted to the floor. Rough diagram below (as viewed from the top, this would be flat, below the baseboard)

    Click image for larger version. 

Name:	52644F54-698E-4876-993C-E39DE8BC2A85.jpg 
Views:	156 
Size:	27.3 KB 
ID:	589471

    ... ideally be paired with a Victron batter monitor (712) and a WRND dcdc.
    Two thoughts:
    1) For the short balancing wires, consider instead of 4 in a row, rather two by two - in a nice block. Busbars are long enough when one does that.
    2) If you have a Victron MPPT with Bluetooth and a BMV with Bluetooth, your can connect the two on a wireless network to share more data.

    https://www.victronenergy.com/live/v...art-networking
    Political Correctness
    Political Correctness is a doctrine, fostered by a delusional illogical minority, rabidly promoted by a unscrupulous mainstream media which holds forth the proposition that it is entirely possible to pick up a turd ... by the clean end!

    Saw this in a pub - no idea why the wife does not see it so:
    I'm not opinionated ... I'm just always right!

  7. #6
    Join Date
    Feb 2013
    Location
    Pretoria
    Age
    31
    Posts
    3,372
    Thanked: 842

    Default Re: Advice on DIY lithium configurations for Jimny!

    Rather than the WRND DC-DC, I'd put in a separate DC-DC charger and MPPT solar controller also Victron. Nice thing about this is that they can communicate as per TTT's post and you don't have to buy everything all at once to ease the budget a bit. Also recently there was quite a few complaints about the newer WRND chargers packing up.

    For example the Victron Orion RT Smart 12/12-18A version should suit your needs just fine, then you can add a solar controller something like the Smartsolar 75/15 depending what panels you get at a later stage.

    As for the BMV712 smart, if you'll be fine with no display and just monitoring via your phone app, then you can also go for just the Victron Smart Shunt, this is practically a BMV712 Smart without a display. Because this install will be in your vehicle, you'll be able to monitor via the app while driving as well.
    It's in pubs where the world's greatest ideas begin.

  8. The Following User Says Thank You to bigboy529 For This Useful Post:


  9. #7
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Can I connect LiFePO4 prismatic cells side by side?

    Quote Originally Posted by the_terrible_triplett View Post
    Two thoughts:
    1) For the short balancing wires, consider instead of 4 in a row, rather two by two - in a nice block. Busbars are long enough when one does that.
    2) If you have a Victron MPPT with Bluetooth and a BMV with Bluetooth, your can connect the two on a wireless network to share more data.

    https://www.victronenergy.com/live/v...art-networking

    Thanks!

    1. Great idea! I have just ordered the batteries, and I think I will have to play around with the layout when it arrives. The cells are 47mm high when flat, and I have a max 61mm height to work within.
    2. Looking into the connectivity...sounds promising!
    Suzuki Jimny (2015)



  10. The Following User Says Thank You to jonnyr For This Useful Post:


  11. #8
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by bigboy529 View Post
    Rather than the WRND DC-DC, I'd put in a separate DC-DC charger and MPPT solar controller also Victron. Nice thing about this is that they can communicate as per TTT's post and you don't have to buy everything all at once to ease the budget a bit. Also recently there was quite a few complaints about the newer WRND chargers packing up.

    For example the Victron Orion RT Smart 12/12-18A version should suit your needs just fine, then you can add a solar controller something like the Smartsolar 75/15 depending what panels you get at a later stage.

    As for the BMV712 smart, if you'll be fine with no display and just monitoring via your phone app, then you can also go for just the Victron Smart Shunt, this is practically a BMV712 Smart without a display. Because this install will be in your vehicle, you'll be able to monitor via the app while driving as well.

    Uncanny. I have just put this down as my new setup 😂 Though I'm thinking of the 30A charger so that I can fully recharge the 120Ah battery in around 4hrs - is my maths correct? (Battery BMS can accept 60A charge, so it shouldn't limit the DC-DC).


    Click image for larger version. 

Name:	Screenshot 2020-09-22 at 10.39.43.png 
Views:	96 
Size:	145.3 KB 
ID:	589587
    The column on the right are the best prices I've found online in SA so far. Who has the best prices on Victron gear?

    This setup is looking like the most attractive option right now. I would like to add the temperature sensor to the shunt, and it seems you can use the sensor information via the shunt > relay > orion remote to switch charging off at a certain low temperature. Not that we need it much in SA, but would be nice to know I can leave everything connected without fear of battery damage by accidentally charging when 0 degrees or less.

    Interested to hear thoughts on this setup.
    Last edited by jonnyr; 2020/09/22 at 10:40 AM.
    Suzuki Jimny (2015)



  12. #9
    Join Date
    Feb 2013
    Location
    Pretoria
    Age
    31
    Posts
    3,372
    Thanked: 842

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by jonnyr View Post
    Uncanny. I have just put this down as my new setup 😂 Though I'm thinking of the 30A charger so that I can fully recharge the 120Ah battery in around 4hrs - is my maths correct? (Battery BMS can accept 60A charge, so it shouldn't limit the DC-DC).


    Click image for larger version. 

Name:	Screenshot 2020-09-22 at 10.39.43.png 
Views:	96 
Size:	145.3 KB 
ID:	589587
    The column on the right are the best prices I've found online in SA so far. Who has the best prices on Victron gear?

    This setup is looking like the most attractive option right now. I would like to add the temperature sensor to the shunt, and it seems you can use the sensor information via the shunt > relay > orion remote to switch charging off at a certain low temperature. Not that we need it much in SA, but would be nice to know I can leave everything connected without fear of battery damage by accidentally charging when 0 degrees or less.

    Interested to hear thoughts on this setup.

    For Victron pricing, try your local Current Automation as well.
    No problem with your thinking to go with the 30A Orion smart, yes charging from 0% SOC where you anyway don't want to go, to 100% SOC should take around 4.5 hours in theory.
    Just check out the Orion Smart manual, if I remember they must be mounted upright with the connections showing to the bottom and also remember it will need some ventilation, they get pretty hot.
    It's in pubs where the world's greatest ideas begin.

  13. #10
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by bigboy529 View Post
    For Victron pricing, try your local Current Automation as well.
    No problem with your thinking to go with the 30A Orion smart, yes charging from 0% SOC where you anyway don't want to go, to 100% SOC should take around 4.5 hours in theory.
    Just check out the Orion Smart manual, if I remember they must be mounted upright with the connections showing to the bottom and also remember it will need some ventilation, they get pretty hot.

    Thanks! Have contacted them and looks like I'll be placing the order today, collecting end of next week.

    Will keep this thread updated with the build.
    Suzuki Jimny (2015)



  14. #11
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    The batteries have arrived! So has the Orion smart 12-12 30 and the Victron Smart Shunt and battery temp sensor.

    I laid it all out under the deck and it seems to be fitting so far, and the BMS cables reach (just) with some slack - so gearing up to do the install soon.

    I'm no electrician, so trying to figure out the circuit flow first. Then I'll measure up cable lengths, calculate cable sizes and count all the other terminals, crimps, fuses and sockets needed etc.

    If anyone out there is good with electrical circuits, I would appreciate feedback on the PDF attached - does it look roughly right?

    Thanks as always 🙏


    Pic of the install location below:
    Click image for larger version. 

Name:	IMG_0473.jpg 
Views:	152 
Size:	285.8 KB 
ID:	591543
    Attached Images Attached Images
    Suzuki Jimny (2015)



  15. #12
    Join Date
    Oct 2013
    Location
    Centurion
    Age
    64
    Posts
    2,039
    Thanked: 755

    Default Re: Advice on DIY lithium configurations for Jimny!

    Very good job done here. All is perfect. You can be consulted for doing a good design.

  16. The Following User Says Thank You to ekkekan For This Useful Post:


  17. #13
    Join Date
    Aug 2009
    Location
    JHB
    Age
    66
    Posts
    965
    Thanked: 187

    Default Re: Advice on DIY lithium configurations for Jimny!

    If I may ask where did you get the batteries and BMS from?
    Your design comes at an opportune time as I am busy rebuilding my packing system.
    Just one thing. I noticed with my old packing system that things got quite warm under the baseboard. Never checked the temp but increased temp was definitely noticeable. Just warm to touch

  18. #14
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by ekkekan View Post
    Very good job done here. All is perfect. You can be consulted for doing a good design.

    PHEW! Good to know all those hours on YouTube paid off hahaha. Also looking for any other suggestions or things to change? Would you do anything differently?
    Suzuki Jimny (2015)



  19. #15
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by Woolf View Post
    If I may ask where did you get the batteries and BMS from?
    Your design comes at an opportune time as I am busy rebuilding my packing system.
    Just one thing. I noticed with my old packing system that things got quite warm under the baseboard. Never checked the temp but increased temp was definitely noticeable. Just warm to touch

    Hey - I bought the 120AH DIY kit from here: https://lithiumbatteriessa.co.za/col...32321360330842
    It included the BMS, busbars, nuts & bolts etc. I have not connected the system up yet so can't say how good it is, but the reviews I've read have been positive for that company.

    I got all the Victron gear through Current Automation - they were quick and pricing was the best I could find.
    Suzuki Jimny (2015)



  20. The Following User Says Thank You to jonnyr For This Useful Post:


  21. #16
    Join Date
    Aug 2009
    Location
    JHB
    Age
    66
    Posts
    965
    Thanked: 187

    Default Re: Advice on DIY lithium configurations for Jimny!

    Oos
    Out of stock
    Last edited by Woolf; 2020/10/09 at 09:40 AM.

  22. #17
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by Woolf View Post
    Oos
    Sorry! Send them an email, they're pretty active and regularly get new shipments in – I'm sure they'd be able to let you know when some more are arriving.
    Suzuki Jimny (2015)



  23. #18
    Join Date
    Aug 2009
    Location
    JHB
    Age
    66
    Posts
    965
    Thanked: 187

    Default Re: Advice on DIY lithium configurations for Jimny!

    Spoke to them. Expecting stock in 2 weeks
    Will preorder

  24. The Following User Says Thank You to Woolf For This Useful Post:


  25. #19
    Join Date
    Oct 2013
    Location
    Centurion
    Age
    64
    Posts
    2,039
    Thanked: 755

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by jonnyr View Post
    PHEW! Good to know all those hours on YouTube paid off hahaha. Also looking for any other suggestions or things to change? Would you do anything differently?
    I would put a fuse on the bat + before it goes to the load switch as that bat can provide a lot of amps. Ensure that you use a very good high quality switch for the load. Not always easy to find. Also having 2 fuses for inside and outside lights close to a overkill. I do notice you have a lot of fuses. This is only as you are asking what I would change.

  26. #20
    Join Date
    Apr 2018
    Location
    Cape Town
    Posts
    49
    Thanked: 14

    Default Re: Advice on DIY lithium configurations for Jimny!

    Quote Originally Posted by ekkekan View Post
    I would put a fuse on the bat + before it goes to the load switch as that bat can provide a lot of amps. Ensure that you use a very good high quality switch for the load. Not always easy to find. Also having 2 fuses for inside and outside lights close to a overkill. I do notice you have a lot of fuses. This is only as you are asking what I would change.
    Haha ok yes – overkill on the fuses - thought it might make troubleshooting easier down the line if stuff started playing up. We don't have half of those accessories yet, just thinking to build the circuit with expansion in mind and guessing what we'd add.

    For now, we have a fridge, a compressor, some usb and cig sockets for charging, and would like to add an inverter soon to recharge/power laptops, cordless drill, coffee grinder


    the Switch from Lithium Battery to 12 load:
    I was thinking of something like this: https://4x4direct.co.za/battery-accessories/6802-isolator-switch-heavy-duty-marine.html
    It can do 200amps continuous, and 400amps peak. The battery can do 1.5C continuous (120ah x 1.5 = 180a) and 3C peak (360a), but the BMS lints output to 120A max - so this should do the trick?
    A bit pricy though. Not sure what the other options would be... maybe a 175A Andersen that I can just disconnect/reconnect?

    *Edit: or maybe just a circuit breaker I can manually disconnect?


    Disconnect from starter to DC-DC:
    This should only be pulling roughly 30A, so a 50a Andersen should be fine here? The point of this is to be able to disconnect the charging system from the starter if I'm doing maintenance etc, but the loads will still run fine of the lithium. Don't know if it's necessary, but the Andersen connection seems to be simple and cheapish option comparatively. In time I'd ideally add the MPPT input next to this, also via a 50a Andersen plug.
    Last edited by jonnyr; 2020/10/09 at 11:27 AM.
    Suzuki Jimny (2015)



Page 1 of 2 1 2 LastLast

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •