Author Topic: Changing from SLA to LifePo4 batteries  (Read 553 times)

0 Members and 1 Guest are viewing this topic.

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #15 on: March 17, 2021, 06:34:55 pm »

I did get one 16s active balancer so unplugged the bms on one 48v set and plugged in the balancer in its place temporarily.  I'll give it a few days and see what results I get with it. 

8904-0
8906-1

Same plug on bms and balancer, but of course they are wired backwards from each other so had to slice off the alignment tabs on the plug to get it to go on the balancer 'backwards' for correct hookup and operation.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #16 on: March 20, 2021, 08:32:08 pm »

It's been 3 days since I added the 16s active balancer.  Hard to tell if things are improving.  Lights come on indicating it is balancing. Lights are out most of the time.  Since the 48v sets don't go much above 54v, they may or may not be doing me any good.  More time needed.

On another note, I put in my order for 8 more of the byd 24v modules.  This time from Battery Clearing house.  These will add to my 48v bank, doubling the size.  Its probably big enough already so this addition should be overkill.  I'm aiming to have enough capacity to handle the short days/long nights of Idaho winters better.

My original modules are the plain type.  The ones on the way are the type with heatsinks and fans attached.  My plain modules don't even get warm (so far) so heatsinks and fans seem superfluous.  Wondering if I can remove them to simplify things and save weight and space?  Besides, I already have a use for the heatsinks....

Anyway, planning to add larger gauge wire for balancing and paralleling the additional 8 modules, ending up with one 16s4p setup that will have one 5a balancer and will then be paralleled to the existing bank.  If the balancing works better that way will probably eventually reconfigure the original 8 the same way (the current setup is 4 sets of 16s1p paralled together, each of the 4 sets balanced separately). 

Then there is the question of the method for balancing.  In discussion with Sid on the Genetry forum, I'm coming to realize the limitations and possibly design flaws of active balancers.  He makes a convincing argument of the possibility of damage caused by some types.  He has designed a shunt balancer system that bleeds off excess cell voltage as heat.  Wasting power but safer for the system.  So if he makes it available soon might try one.

Keeping these modules balanced as much as possible seems to be the key to them lasting a long time.  I knew nothing about lithium when I started, have learned a great deal in a short time, and still know very little.  Working on it, though....
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #17 on: April 06, 2021, 03:08:02 pm »
It's been a few days since I attached the 16s 1.2a active balancer on one leg of my 48v bank.  It seems to be an improvement over the bms, but only a slight improvement.  Planning to go ahead with paralleling all the cells and then attaching a 16s 5a active balancer.  The installed original balance wires should handle it ok, especially since the bank doesn't go above 54.4v.  Might gradually increase voltage after some settling-in time.  We'll see.

Also got and installed the 4 remaining 8s 1.2a balancers on my 24v bank byd modules.  Each module now has one balancer, plus one of the cellmeter8 gadgets so I can tell what's going on.  It's been a few days and they seem to be doing ok.  Above 27v they still go somewhat out of balance but probably good enough for my needs.  Still could parallel all of the cells on these but not right away.

My shipment of 8 additional byd modules is scheduled to arrive today.  Waiting (mostly) patiently.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #18 on: April 06, 2021, 08:33:37 pm »
Here's a pic of my 24v bank with active balancer and cellmeter on each module;

8910-0

The next two are front and back of the 5a balancer to be installed on the 48v bank;

8912-1
8914-2

An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #19 on: April 08, 2021, 08:36:56 pm »

The 8 additional byd 24v modules finally arrived.  I have already started removing the heatsinks on one.

8916-0
8918-1

These heatsinks are massive!  They are 1.5 inches thick, 21 inches long and 12 wide.  They must weigh 10-20 pounds each. 

8920-2
8922-3

Then there is a high speed 24v fan on each module.  They must have really used these modules under heavy loads to need such massive cooling power.  My existing set of modules has not even gotten warm to the touch, and they are the version with no heatsinks/fans.  Hence my removing the heatsinks on these.  I don't expect these to get warm either, especially since I'm adding them to the existing set which already stays cool.

Besides the reduction in weight, removing the heatsinks reduces the overall size of each module to approximately the same size as the original set.  I have limited space where these are going.  My first set of modules just barely fits so I had to make the new ones fit also.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline Pete

  • Sr. Member
  • ****
  • Posts: 261
  • Karma: +17/-0
  • Mount Barrow Tasmania
Re: Changing from SLA to LifePo4 batteries
« Reply #20 on: April 09, 2021, 02:26:36 am »
Hope they work out for you Doc.
It seems that using lithium batteries is a very complicated process. I hope that they last a long time.
You are on your way to becoming an in house expert on these things
Good luck
Pete

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #21 on: April 12, 2021, 09:24:23 pm »

Thanks Pete,
I'm learning as I go, definitely not an expert. 
I've been busy with other chores, but have gotten two of the eight stripped down.  (Heatsinks, fans and covers removed)  Also have added wires attached to each cell to be used for paralleling all the cells. Also eliminated the inconvenient round posts for positive and negative connections.  These modules are a bit different from the other modules I'm already using.  With these I can remove the round posts and just use the double bolts where the posts were mounted. Much handier. Saves me cash too as I don't need to buy the large copper lugs to adapt the round posts.  A definite plus!   Also, removed an internal busbar that I'm hoping to use for paralleling the modules.  I think they are tinned copper so should work well.  These modules must originally have been much more expensive than the other simpler type I bought the first time, considering all the extra parts.  Same cells, just more 'optional equipment'.  I suppose the 'simple' version would have been intended for a temperature controlled environment.

So, two are ready to move downstairs.  Six to go.  I'm doing this stuff in my garage.  My poor pickup is sitting outside until I'm done with the modules.

On another note, the heatsinks are interesting.  They seem to be two pieces pop-riveted together.  A normal heatsink you would expect to see one flat side and one side with fins.  These have a second flat plate over the finned side.  The air has to move through this 'tunnel'.  It would be difficult for me to use them like this.  So, I drilled out the rivets on one but haven't been able to separate the two parts so far.

I'll get some more pics up soon.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #22 on: April 13, 2021, 08:36:49 pm »

Finally got one of the heatsinks separated.  Turns out the two pieces were glued together as well as pop riveted.  I left a heatsink bolted to a module to give me leverage to pry it apart.  It was still a bear.  Bent a fin or two.  Nothing serious.  Not sure how I'm going to get the glue off as it feels like hard plastic.  Maybe I'll heat it with a torch to soften it.  Anyway, the part with the fins looks all gray in the pics due to the glue/plastic.

8924-0
8926-1
8928-2

Three of the modules are now ready to move and be installed.  Pics show wires sticking out.  I'm adding these to let me parallel all the cells between modules after they are mounted and just before they are hooked up to solar.  Also you can see that I have removed the round posts and will be using the double bolts on the top corners.  This top view will be the front when they are laid down in their resting positions.  Two stacks of four modules side by side.

8930-3
8932-4

The negative round post was connected to the actual negative terminal by these two busbars.

8934-5

The skinny looking busbar is what I plan to use for paralleling the four modules in each stack.  Hate to waste stuff. 
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #23 on: April 14, 2021, 10:22:19 pm »
Was looking a bit closer at that busbar.  Looks black in the pics.  It appears to be triple wrapped with electric tape!  It was mounted where it could make a spectacular short to the cell connections, so I can see why the tape.  Someone spent quite awhile just taping!
I'm still amazed how much work/money and how many extra parts went into making these modules temperature regulated with the fan/heatsink setup.  These must have cost twice as much as the simpler versions originally.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #24 on: April 25, 2021, 06:15:09 pm »

Still working on the byd packs.  Adding wires for paralleling and removing extra parts like fan and heatsinks.  Two to go.
Then I have to mount a terminal strip on the front face of each pack and connect up the wires.

I finally got the glue/plastic/whatever it was burned off of the finned half of the one heatsink I separated.  Gave up on the small torch.  Took nearly 30 minutes to melt off just half of it.  Got out my weed burning rig and finished the rest in a few minutes.

My shunt balancers were finally available from Genetry so got them ordered.  Genetry is famous for its terrible shipping record so no telling how long till they get here.  The heatsink is now ready.  Just need to finish the prep work on the byd packs/modules and get them moved to position.  Then the fun part!  I have to rig the chainfall to lift them into final resting/mounting place.  Will need to build a custom ramp also like for the first set.

When that's all done I can start connecting them up to solar, and finally in parallel to the other set.  Somewhere in there I will be connecting up the shunt balancer setup to the whole set.  Lots of fun ahead!
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #25 on: April 27, 2021, 07:03:36 pm »

All eight of the byd modules are now stripped down and wires for balancing/paralleling added.  Yay!
Now I'm figuring out how I want to mount the terminal strips on each module.  I was going to do that after I got them rigged into place, but realized I won't be able to easily remove and replace the pop-on covers once the modules are in place.  So have to do it now.  It means the modules will be more delicate while I'm moving/rigging them into position.  Oh well.
I had 3 or 4 different ideas on how and where to mount that terminal strip.  Looks like it will be right on the 'front' of the module mounted to one of the pop on panels.  One terminal strip on each module.  Then I will interconnect the modules when they are in place downstairs.  I'll post some pics once I get some done.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #26 on: April 29, 2021, 08:24:25 pm »

Made some progress in between irrigation work today.  Terminal strip mounted on all 8 modules.  4 of those wired up and ready to move downstairs.
8946-0
8948-1


 
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline lighthunter

  • Full Member
  • ***
  • Posts: 229
  • Karma: +11/-0
Re: Changing from SLA to LifePo4 batteries
« Reply #27 on: May 01, 2021, 12:17:08 pm »
Hi Doc! looks like fun project is going well.
How do you like the performance of em compared to lead acid?

If lead acid is big enough and healthy enough they do work well also but lead acid is less forgiving on an undersize bank.

How did you do on price? Of course price is subjective anyway with brand cross comparison.   The last ones i bought were $1280 for 160AH at 51.2v or 15.6¢/wh the first ones i bought were 48.8¢/wh,  i see you can get littokala new for about 20¢/wh
Both that i got tested true to advertised rating but cycle life was 4000 on the more expensive ones only 2000 on the cheapee.
ones. I just like to keep an eye open because the cheap deals arent always cheap but there are better deals.

LH
LH

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #28 on: May 02, 2021, 10:27:34 am »

Hi LH!

Quote
How do you like the performance of em compared to lead acid?
They are so much better it's hard to compare.  Much less fluctuation of voltage, which is easier on the inverter, and helps keep the inverter's output steadier too.  With less up and down, the inverter seems to run cooler too.  The more narrow voltage operating range worried me at first, but as just stated turns into an advantage overall.
If someone offered me brand new top-of-the-line 200ah SLA/AGM batteries and offered to do the work to change them out, I would decline instantly.

Quote
How did you do on price?
My first set of 10 BYD modules were $275 each plus flat $350 shipping from Battery hookup.  Second set of 8 were $295 each with $300 flat shpping from Battery clearing house.
It's hard to judge the price per wh with used modules, but I think it was a very good deal overall.  You can't currently get that price for the BYD any longer except for a local pickup price (and North Carolina is too far for me)
As long as these hold up I have plenty for my needs so I'm good.

I would be interested to know how much these BYD modules cost back when they were new.  Must have been a fortune!
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --

Offline dochubert

  • Full Member
  • ***
  • Posts: 205
  • Karma: +3/-0
  • 11 powerjacks, 9 that run, 3 actually used daily
Re: Changing from SLA to LifePo4 batteries
« Reply #29 on: May 12, 2021, 04:19:16 pm »
Made first attempt at lifting battery modules in place.  Unsucessful.

9001-0
9003-1

The wood 'ramp' was too flimsy and not anchored well enough.

9005-2
9007-3

Got the set lifted but couldn't make the shift over to the shelf.  Set it back down.

Plan B.
Reconfigured the lift cart to give me a few more inches of lift height.  Eliminating the wood ramp.  Moving the chainfall anchor point in closer to the shelf.  Will be trying to lift again shortly.
An illegitimate head of government based on a stolen election.
An illegitimate and corrupt legislation rubber stamped a stolen election and is currently demonizing anyone questioning it.
A corrupt court system that refuses to examine mountains of evidence.

USA = Banana Republic

---  dochubert --