Going Lithium... Wish me luck...

[wamcneil]

Well, my 5yr old GC batteries are toast. So rather then buy more GC batteries I'm going to Lifepo4. 

Last week I did my first transaction on Alibaba and ordered two custom 272AH 12v Lifepo4 batteries to be built. It's a pretty reputable Chinese battery builder that has been supplying a lot of DIY components and batteries for solar forum users. Fingers crossed that they turn out nice and SAFE. 

It'll be several weeks before they arrive, but I'll update this thread as I disassemble, evaluate, test and review them.

The specs for each battery include 4 272AH 3.2v Lifepo4 prismatic cells and a 300a BMS in a steel box.

Wish me luck...

Cheers,

Walter

[Harvey Babb]

I will be watching with interest!

I'm particularly interested in what you plan to use for a power converter/charger. I haven't done any extensive research, but all that I have looked at are designed to operate at a higher voltage than is advisable with LiFePO4 batteries. The three-stage charge regime used by lead acid batteries does not fit with the lithium chemistry. Lithium batteries are usually charged with constant current followed by constant voltage.

 

[wamcneil]

Getting the right charging voltages should be pretty easy with any kind of modern configurable charger. 

I've got a Magnum MS inverter and a Morningstar MPPT solar charge controller. Both of those have fully customizable setpoints.  

The engine alternator is the part I haven't fully figured out yet. In the short term, I might just remove the battery combiners, isolate the chassis from the house batteries and figure it out later. Maybe install a small battery charger to maintain the chassis batteries and then think about adding a DC-DC charger.

Cheers,

Walter

Edited November 25, 2020 by wamcneil

[RVSSNAKE]

This guy/kid Will Prowse seems to really do his research and reviews all types of cells for just our type of usages.

Might be worth a look at his channel.

https://www.youtube.com/channel/UCoj6RxIAQq8kmJme-5dnN0Q

Hopefully the link works, if not just copy and paste into browser.

[wamcneil]

Yeah, he’s got a really good forum too: diysolarforum.com 

Will and the other battery builders on the forum have dumped a lot of knowledge on there.  I had planned to build them myself, but the assembled batteries aren’t much more than the components.  
Cheers

Walter 

[wamcneil]

Getting closer... The batteries are built and waiting for shipment!

[Hotrod - R.I.P.]

On 11/24/2020 at 10:29 AM, wamcneil said:

Well, my 5yr old GC batteries are toast. So rather then buy more GC batteries I'm going to Lifepo4. 

Last week I did my first transaction on Alibaba and ordered two custom 272AH 12v Lifepo4 batteries to be built. It's a pretty reputable Chinese battery builder that has been supplying a lot of DIY components and batteries for solar forum users. Fingers crossed that they turn out nice and SAFE. 

It'll be several weeks before they arrive, but I'll update this thread as I disassemble, evaluate, test and review them.

The specs for each battery include 4 272AH 3.2v Lifepo4 prismatic cells and a 300a BMS in a steel box.

Wish me luck...

Cheers,

Walter

Let us know how it goes. I’m going lifepo4 if my agms ever wear out. Been seeing price down to about 80$ for 280ah cells. Could diy 4 cells and bms and box and freight for probably about 600$ which is in line with agm price . Two of them should do it. Might be able to get three of them , 840ah , on one deck. Cut out a bunch of lead weight.

Bill G 06 Dynasty

 

On 11/30/2020 at 10:00 AM, wamcneil said:

Getting closer... The batteries are built and waiting for shipment!

Look nice . How much ? With freight .

[wamcneil]

$643 each. Total cost for two batteries including shipping is $1519. Ordered from Shenzhen Xuba. I haven't found anybody with experience with their assembled batteries, but a lot of folks on diysolarforums have purchased the 272/280 AH cells from them and reported good service. They'll customize them any way you want.

I'll take them apart when they arrive and post some pictures inside. 

Cheers,

Walter

[Hotrod - R.I.P.]

7 hours ago, wamcneil said:

$643 each. Total cost for two batteries including shipping is $1519. Ordered from Shenzhen Xuba. I haven't found anybody with experience with their assembled batteries, but a lot of folks on diysolarforums have purchased the 272/280 AH cells from them and reported good service. They'll customize them any way you want.

I'll take them apart when they arrive and post some pictures inside. 

Cheers,

Walter

They look real nice. I would be interested in the dimensions to see how many I could put on a deck.

Bill G 06 Dynasty 

 

 

[wamcneil]

The boxes can be customized. I think their default box is 400mm long, but I need it a bit shorter. Asked for box dimensions  360mm (l)x 200mm(w)x 250mm(h) and they agreed to that. They normally use Anderson connectors coming out the top, but I specified side terminals. 
Cheers

Walter

[wamcneil]

14 hours ago, Hotrod said:

They look real nice. I would be interested in the dimensions to see how many I could put on a deck.

Bill G 06 Dynasty 

 

 

I think you could get four 200 AH cells into a case the size of a golf cart battery. Or the case could be much bigger to accommodate 8 cells (~360mmx400mm?). As long as you don't mind the bigger/heavier battery... Lots of options.

[wamcneil]

Getting closer... Batteries have been shipped.

This is my first order on Alibaba. If anybody is curious, here's the way it works. You enter into a contract with supplier, supplier is paid. Alibaba then tracks the order progress and can refund buyer if the order doesn't arrive as agreed or doesn't conform to the contract.

In the negotiations, I had to ask for them to update the contract terms to include specifics on the custom battery capacity, dimensions and layout. They started the order based on their 200ah listing item with different dimensions and Anderson connectors. Upon request, they created a new listing and then assigned that to the contract.

Communication responses are prompt, but it's apparent that their English is just slightly better than my Chinese...  

[wamcneil]

Ugh. Almost 2 months later... and batteries still not arrived.

They cleared customs, and then sat in the port in CA for couple weeks. Now finally in the possession of UPS and will arrive next week!  

[gofastnow]

On 11/25/2020 at 10:42 AM, wamcneil said:

Getting the right charging voltages should be pretty easy with any kind of modern configurable charger. 

I've got a Magnum MS inverter and a Morningstar MPPT solar charge controller. Both of those have fully customizable setpoints.  

The engine alternator is the part I haven't fully figured out yet. In the short term, I might just remove the battery combiners, isolate the chassis from the house batteries and figure it out later. Maybe install a small battery charger to maintain the chassis batteries and then think about adding a DC-DC charger.

Cheers,

Walter

Walter, if your coach has an external alternator regulator you may want to look at Balmar MC-614 Regulator for control of the alternator. I do not have any first hand experience with this regulator but the info looks pretty good. If I were to go this route, I would opt for the alternator temp sensor to try to keep from frying the alternator as those Lithiums will suck down all the current most alternators can produce.

Cheers and good luck

[Hotrod - R.I.P.]

2 hours ago, gofastnow said:

Walter, if your coach has an external alternator regulator you may want to look at Balmar MC-614 Regulator for control of the alternator. I do not have any first hand experience with this regulator but the info looks pretty good. If I were to go this route, I would opt for the alternator temp sensor to try to keep from frying the alternator as those Lithiums will suck down all the current most alternators can produce.

Cheers and good luck

Renolgy makes dc to dc chargers in 20, 40 and 60a that should do a good job of charging them from the chassis side and have lithium profiles. They have an input from the ignition to let it know that the engine is running .  Amazon has them . 

I think you could still use a big boy for a boost. You could put a separate smart charger on the chassis batteries to maintain them w shore power. 
 

Bill G 06 Dynasty 

[wamcneil]

Well, I’m hoping I don’t need to rapid-charge the batteries from the alternator, so no plan to modify the alternator at this point. 
DC/DC charger is on the short list.
But initially I’ll just isolate the house from chassis and see how that works out. 
I figure I won’t be running a lot of house loads while underway, and I should still have solar underway too. So maybe I can just keep them isolated (except for the combiner relay).
Ive got a small battery maintainer to plug into the block heater outlet to keep the chassis batteries charged while parked. 
2 more days till the batteries arrive!

Cheers

Walter

[Dr4Film]

I have a close friend from Washington who has installed LiPo batteries in his coach for the house but he doesn't post much on this forum. Don't know that much about his installation or charging system but I do know that since he does a lot of winter camping with his coach to go skiing he did insulate the battery compartment and installed a bay warmer to keep the batteries above a certain temperature in cold climates.

Also, I have a LiPo battery in my motorcycle (Anti-gravity Re-Start Lithium Battery ATX-20 680CA 4 Terminal) and this is the charger that I keep on it when gone for the summer.

https://tinyurl.com/2vbtsxzb

 

[wamcneil]

Today's the day!!! 2-1/2 months later... Batteries are on the UPS truck for delivery.

[jfbolkovatz]

I purchased in October 2 - 400AH, 200A discharge, 100A charge rate Batteries, The coaches Trace charger is 160A. I purchased 2 , installed them in parallel. For a 800AH setup. Tested them as shown on you tube videos.  14.5V to 11.6V similar test each. Results.  5.25-5.2KWH,  409- 416 AH.  Started discharge test At 14,5V with a heat gun and 1500W inverter. Discharged at 92A for 4.4hrs approx each. 14.5V to 13.6 about 25 minutes then 3:15 minutes to 12.6V. Amps dropped to 12.1V and shut off the inverter, Changed to a 600W heater draw to reduce the amp draw and discharged for about 20 additional minutes to ll.6V.

My issue was the restricted space needed 16.9 inches by 14.6 inches. Delong in China was the only one who would sell this size with a 200A continuous discharge rate. I added another extendable Kwickee tray also. Battery low temp protection with heating pads. Alt protection with a 40A DC to DC charger.

Have not fully tested the complete setup, first trip in April, and I'll report.

JoeB 03 Exec PBDD.

[wamcneil]

Nice. Interested to hear how they do on the trip.

[Hotrod - R.I.P.]

52 minutes ago, jfbolkovatz said:

I purchased in October 2 - 400AH, 200A discharge, 100A charge rate Batteries, The coaches Trace charger is 160A. I purchased 2 , installed them in parallel. For a 800AH setup. Tested them as shown on you tube videos.  14.5V to 11.6V similar test each. Results.  5.25-5.2KWH,  409- 416 AH.  Started discharge test At 14,5V with a heat gun and 1500W inverter. Discharged at 92A for 4.4hrs approx each. 14.5V to 13.6 about 25 minutes then 3:15 minutes to 12.6V. Amps dropped to 12.1V and shut off the inverter, Changed to a 600W heater draw to reduce the amp draw and discharged for about 20 additional minutes to ll.6V.

My issue was the restricted space needed 16.9 inches by 14.6 inches. Delong in China was the only one who would sell this size with a 200A continuous discharge rate. I added another extendable Kwickee tray also. Battery low temp protection with heating pads. Alt protection with a 40A DC to DC charger.

Have not fully tested the complete setup, first trip in April, and I'll report.

JoeB 03 Exec PBDD.

Sounds great Joe,  Do you still have the boost relay and can you use it without tripping the overload on the bms ? 
 

And what are you going to do to charge the chassis batts from the house when it has shore or genny. 
 

Does the charger have any lithium profile or just treating them like lead? Got any way to take them to full charge ? 

Bill g 06 dynasty

Just now, Hotrod said:

Sounds great Joe,  Do you still have the boost relay and can you use it without tripping the overload on the bms ? 
 

And what are you going to do to charge the chassis batts from the house when it has shore or genny. 
 

Does the charger have any lithium profile or just treating them like lead? Got any way to take them to full charge ? 

Bill g 06 dynasty

Actually I guess your dc to dc will take them to full charge if you drive long enough . 
 

bill g 06 dynasty

[wamcneil]

They're here! The box is very nice and tidy. All the seams welded, rivnuts on the fasteners. And the box is built exactly to my dimensions. 

Everything is glued together inside so I can't get a good look at the cells without peeling it all apart.

The BMS is about the only part I can get to without peeling away a bunch of adhesive, foam and insulating panels. It's locates on the top.

The BMS appears to be adequate.. It's 'advertised' as:

• Continuous charging current: 100A
• Continuous discharge current: 300A
• Maximum charging current: 150A
• Maximum charging voltage: 14.6A
• Minimum discharge voltage: 10V
• Low temperature protection
• Charging protection
• Automatic balancing

I'm sure the discharge current is highly exaggerated. The BMS main conductors are twin 8-ga wires.

They're charging now. Will probably be balancing the cells and testing the BMS over the next few days.

[jfbolkovatz]

On 2/3/2021 at 1:19 PM, Hotrod said:

Sounds great Joe,  Do you still have the boost relay and can you use it without tripping the overload on the bms ? 
 

And what are you going to do to charge the chassis batts from the house when it has shore or genny. 
 

Does the charger have any lithium profile or just treating them like lead? Got any way to take them to full charge ? 

Bill g 06 dynasty

Actually I guess your dc to dc will take them to full charge if you drive long enough . 
 

bill g 06 dynasty

Bill, the the DC TO DC connects to the alternator chasse battery post, thru the converter to the house post. with the house batteries above 13.2V approx. the maintainer will charge the chasse batteries. With full normal draw the house batteries should last 4-6 days before needing the generator to recharge both.

[JDCrow]

Following 

[wamcneil]

I guess I should update... In general I'm really liking lithium batteries. But there have been some snags.

As I dug into the batteries I found some serious problems with the construction. And after complaining to Xuba came to find they subcontracted construction to another company who was responsible for the shoddy assembly.  Eventually came to the agreement that Xuba would find another contractor, carefully design a better-engineered 'product' version of the batteries and manufacture replacements. 

So that's where we are now. Xuba appears to be acting in good faith. The replacements should be done with assembly any day now and probably couple-months in shipping before I get them.

Meanwhile, the batteries are working, but some of the connections inside have high resistance, and I'm having to work around limited current in and out of the batteries.  

Hopefully I'll be able to report wonderful customer service at Xuba and eventually getting the batteries of my dreams, but it's still in process at this point.

Cheers,

Walter