Lithium LifePo4 cells price drop!

[waterskier_1]

55 minutes ago, Dear LaserWorks said:

Rick, how do you wire in a DC-DC charger and retain the ability to boost with both batteries if needed?

There is no elegant solution test I know of.   I'm not at much computer right now, so not sure what you currently have.  If you are only looking for boost, you might be able to use what the coach came with, but inhibit the alternator charging of the house battery.  If,  on the other hand, you are looking to charge the chassis from the house lithium batteries, the only thing I can think of is Amp-L- Start or Echo Start type device, and I'm not sure about that due to voltage differences.  I personally only have the boost function, but use solar for charging my chassis when not driving. 

[Ivylog]

When I built 6-100AH batteries out of 26 cells I matched them up and kept the 2 extra as spares if a cell goes bad. With only 8 cells it will be harder to get as good a match.

At the current prices, I really don’t care that a 310AH cell is only 300AH. Over time a BMS will match the cells within the battery.

Less than a year ago it cost me $1200 to build 600AH of Lithiums. Today for $1200 I can build 1200+AH.

 

Edited September 30, 2021 by Ivylog

[waterskier_1]

16 hours ago, Dear LaserWorks said:

Rick, how do you wire in a DC-DC charger and retain the ability to boost with both batteries if needed?

I have looked at the wiring diagrams I have.  I don't have a good copy for 2000 Diplomat, but found one for a 2002 which I think is the same as far as the Boost Circuit goes.  I believe the purple wire going to the Isolator Relay (R6 in my drawing) is the input from the Boost Switch on the Dash.  That Isolation Relay connects the Chassis and House Batteries together.  It is there primarily to charge the house batteries from the alternator, and secondarily to add the Boost function.  The Red wire from the Isolator Delay Module which has a yellow wire going up the the FRB is the control to make the Isolator Relay connect both sets of batteries together.  You no longer want that function (alternator charging the house batteries) so that wire should be removed from the Isolator Relay and securely taped or better yet heat shrink over the end so it can't short out.  That will leave only the 16 gauge purple (violet) wire on one terminal, a ground wire on another, and the two big 2/0 Red cables, one to each battery bank connected to the Isolator Relay.  This will allow the Boost switch to engage that Isolator Relay, but not the alternator charging circuit.  

One thing to note, most people are replacing this relay with the Blue Sea ML-ACR device, which does have a feature called Boost, but it won't work with the DC/DC Charger installed.  I realize that this isn't the greatest way to accomplish your goal of Boost, but it doesn't require any new hardware.  

If it were me, I'd just carry a set of Jumper Cables, and jump the two batteries together if that is ever needed.  To be perfectly honest, the only time I had to do this, and I did not have Lithium batteries for the house yet, I used my Jeep to jump the chassis battery.  In that case, my Chassis batteries (2- 12Volt) were shot, and I was dry camping and didn't want to use my house batteries, and wasn't sure they would jump my Detroit Diesel in any case.  

Please ask if you have more questions.

[Dear LaserWorks]

10 hours ago, waterskier_1 said:

I have looked at the wiring diagrams I have.  I don't have a good copy for 2000 Diplomat, but found one for a 2002 which I think is the same as far as the Boost Circuit goes.  I believe the purple wire going to the Isolator Relay (R6 in my drawing) is the input from the Boost Switch on the Dash.  That Isolation Relay connects the Chassis and House Batteries together.  It is there primarily to charge the house batteries from the alternator, and secondarily to add the Boost function.  The Red wire from the Isolator Delay Module which has a yellow wire going up the the FRB is the control to make the Isolator Relay connect both sets of batteries together.  You no longer want that function (alternator charging the house batteries) so that wire should be removed from the Isolator Relay and securely taped or better yet heat shrink over the end so it can't short out.  That will leave only the 16 gauge purple (violet) wire on one terminal, a ground wire on another, and the two big 2/0 Red cables, one to each battery bank connected to the Isolator Relay.  This will allow the Boost switch to engage that Isolator Relay, but not the alternator charging circuit.  

One thing to note, most people are replacing this relay with the Blue Sea ML-ACR device, which does have a feature called Boost, but it won't work with the DC/DC Charger installed.  I realize that this isn't the greatest way to accomplish your goal of Boost, but it doesn't require any new hardware.  

If it were me, I'd just carry a set of Jumper Cables, and jump the two batteries together if that is ever needed.  To be perfectly honest, the only time I had to do this, and I did not have Lithium batteries for the house yet, I used my Jeep to jump the chassis battery.  In that case, my Chassis batteries (2- 12Volt) were shot, and I was dry camping and didn't want to use my house batteries, and wasn't sure they would jump my Detroit Diesel in any case.  

Please ask if you have more questions.

Thanks! We already carry a set of jumper cables, so that would work. Appreciate the input.

[waterskier_1]

10 hours ago, Dear LaserWorks said:

Thanks! We already carry a set of jumper cables, so that would work. Appreciate the input.

One other thing - since I live in Colorado and shore my coach in my side yard. In the winter we may have snow that lasts for days on the solar panels, and that is the only way to charge the chassis battery (one slat panel dedicated to the chassis panel).  To make sure the chassis battery is always maintained, I installed a cheap battery maintainer.  It is only used when the coach is stored.  I plug it into the Block Heater outlet in the engine bay.  I never use the block heater.  When I get ready to depart in January, I start up the Aquahot a day or two before to warm up the coach, and use the engine pre- heat to warm the engine.  This might be an option for you when you have shore power.  Note: I haven't studied the Amp-L-Start or Echo Start type products for use with Lithium batteries.  My initial thought is not to use them. 

[Ivylog]

2 hours ago, waterskier_1 said:

haven't studied the Amp-L-Start or Echo Start type products for use with Lithium batteries.  My initial thought is not to use them. 

When in storage you only want Lithiums at 50-60% charge. IF the Amp-Echo charge voltage is only 13.15 (Lithiums 50% voltage) they could be left on all the time. Like AGMs, Lithiums do not self discharge like L-A batteries.

If you do not dry camp and only go from FHU to FHU CGs, you only need one 12V AGM (no watering) house battery… no need to go Lithiums.

[waterskier_1]

38 minutes ago, Ivylog said:

When in storage you only want Lithiums at 50-60% charge. IF the Amp-Echo charge voltage is only 13.15 (Lithiums 50% voltage) they could be left on all the time. Like AGMs, Lithiums do not self discharge like L-A batteries.

If you do not dry camp and only go from FHU to FHU CGs, you only need one 12V AGM (no watering) house battery… no need to go Lithiums.

I just noticed that Amp-L-Start has a new version (Revision G5) that can be set up for Lithium batteries.  I think this would be the way to go if I wanted to be able to maintain the chassis battery from the house battery.  The main reason I say this is because it also allows you to maintain the chassis batteries when only on solar.  

[Ivylog]

Undate: the BMSs arrived in 2 weeks (air freight) but no telling when the cells will arrive because of the current shipping backup. 
Sale starting on the 25th has 8 320AH cells for $328. For those wanting grade A cells, 4 200AH are the same price.

[cbr046]

I read an article where a guy out west is buying used Nissan battery cells and using them to build a solar battery farm to sell power back to the utility.  It must be working because he has multiple stations already running and building more.  Biggest savings are the used Nissan cells.  One mans junk, another man's treasure. 

So that got me to thinking . . . . are there used auto cells that can be broken down, modified & adopted for coach use?  That would really bring the price down and we don't need A grade quality.

- bob

 

[Ivylog]

Two problems…400 volts and fire prone LiMn2O4/LiNiO2 chemistry. 400V can be solved by enough panels in series but then shading becomes a issue.

[cbr046]

7 minutes ago, Ivylog said:

fire prone LiMn2O4/LiNiO2 chemistry.

That would be a quick end.

- bob

[Ivylog]

UPDATE: we’ll it was too good to be true… cells never showed up and I missed the deadline to dispute the 280 AH cells but I did dispute the 310AH in time. After some back and forth with Ali I was able to start a chat with their dispute resolution person…Ronnie. Fortunately I had screenshots of some of the delivery info that was fictitious and Ronnie refunded all of my $$ on both sets of batteries that never showed up.

Been watching for cells (less than $2/AH)  and even completed batteries. The cheaper batteries tend to have to low a amp BMS for the “rated” capacity.

Just ordered 3 180AH Varicore batteries for $2.08/AH. While the BMS is only rated 50A in and 100A out, three of them matches my 3012 inverter/charger…150A out and 300A in. I’ll combine these with the 600AH of Lithiums I built a year ago for $2/AH and use my 100A addition charger and 80A of solar to charge them.

[wamcneil]

I hope this one works out!

Alibaba is a crap shoot… I’ve had some really good customer service from Xuba on alibaba.  They made me a custom pair of assembled batteries for a pretty attractive price. Long story, but the first set had some shoddy assembly and they replaced them altogether with very nicely built batteries. And I didn’t need to file a claim with alibaba trade assurance. I’ve purchased more cells from them since. 
Cheers

Walter

[waterskier_1]

2 hours ago, wamcneil said:

I hope this one works out!

Alibaba is a crap shoot… I’ve had some really good customer service from Xuba on alibaba.  They made me a custom pair of assembled batteries for a pretty attractive price. Long story, but the first set had some shoddy assembly and they replaced them altogether with very nicely built batteries. And I didn’t need to file a claim with alibaba trade assurance. I’ve purchased more cells from them since. 
Cheers

Walter

I am not sure it's a total crap shoot.  If you do your due diligence and review manufacturers and their quality reviews, just as you would if buying at a local brick & mortar  store, you'll get reasonable results.  On the other hand, if you are looking to buy seconds, or items that the manufacturer has rejected for not complying fully with their specifications, you may be disappointed. This is especially true when you can not inspect before purchase, and returns are costly, if even available.  

I have studied LiFePO4 cells for months, including the manufacturers and their quality as reported by purchasers.  I don't want to buy 12 nonconforming cells to find 8 good enough cells to make a battery(s).  I ordered directly from the manufacturer, via Alibaba based upon many reviews of their product meeting or exceeding purchasers expectations.  I discussed with their sales rep and their engineer letting them know what exactly I wanted.  They recommended their A+ cells, which exceed their specifications, and include full testing results for each cell.  They sold them as 285 AHr A+ cells, but said they tested to more than 315 AHrs.  I didn't care about the 30 AHr difference, but was assured they were their very best quality cells.  I have only tested them to 275 AHr because I forgot to change my inverter setting to allow discharge below 11.0 volts.  I'm quite sure they would meet the spec requirements, and meet my expectations fully.  If I'm going to spend money and my time building something, I want to start with quality materials.  

My research also led me to seek out the best BMS.  Many claim to have full functional control, but do not, or are not programmable.  I would not buy a LiFePO4 battery (as opposed to cells that I make into a battery) because many don't meet their claims, or don't even discuss the setting of their internal BMS.  

My opinion, YMMV.

  -Rick N.

[Ivylog]

I agree there’s a good possibility that these batteries will fall short of meeting their rated power and even 3000 cycles but I do not need 900AH of batteries and at 60 cycles/year, doubt I’ll make it to 120. At $2/AH (or anything close) it makes them cheaper than AGM, especially if you might need 2000 cycles.

Edited April 2, 2022 by Ivylog

[trstaska]

On 9/27/2021 at 4:04 PM, Dear LaserWorks said:

.

I'm not a DIYer when it comes to lithium batteries.  Can anyone tell me where I can get a lithium setup installed in my 2006 Dip at a reasonable cost by someone who knows what they are doing!!