LiFePo4 "upgrade" in progess.

[rickst29]

With two batteries, things have changed a bit. https://www.trailmanorowners.com/for...12&postcount=9

[rickst29]

Originally Posted by Bill

I'm sorry to hear that. I was looking forward to hearing good reportsl and learning more about LiFePO4. Chinese, of course. I'm not sure what excuse they will use. Probably something about end-of-life voltage being 10.0 volts instead of 12.8 volts.

I noticed that one of the reviews described exactly what you are experiencing.
Buyer beware these are 50ah batteries with a 100ah sticker. I tested all 3 batteries I ordered and the all tested to 51 ah.These are a rip off. .

Good luck, and let us know the outcome.

I also saw that review (after my battery had been shipped), although his batteries were not the same as mine (he may not have measured as carefully). Seller will not dare to use that "if you ran it down to 10V then you would be getting all of it" excuse, because the SOC for LiFePO4 cells follows a very reliable curve when near-static discharge voltage begins to fall off in standard temperature conditions (that is, under 12.4V for a 4-cell battery, 3.1V per cell).

If we assume '100Ah' USA-built batteries to be genuine 100 Ah batteries, then the full price (for a 60Ah battery) is still better-than-competitive: Instead of $900 for 100Ah built in USA, I paid about $425 for 60Ah. ($7.08 per Ah, compared to $9.00 plus higher ancillary costs for buying within the USA). But it takes more boxes and more wiring to get the capacity you want. After I plug this one in, I end up with about 160Ah total capacity, about 135 consistently usable before I begin to degrade battery lifespan (by discharging "too far").

But full price turns out to be irrelevant. When I sent my test report as a message to the seller, he checked and replied that the 'wrong battery' had been built and sent to me. With about 30% of my "minimum 90 Ah to be measured" missing, he agreed immediately to refund $150 of the payment back to me, saying that the problem was entirely at his end. (I don't know the story with that other buyer, and he may not have taken advantage of DHGate escrow and problem resolution processes,)

At DHGate, payments are held in escrow until the buyer confirms that the item has been received in good condition (which I did not do, opening an "Item Not As Described" resolution request instead). Seller and I exchanged friendly and effective messages, I have left a very long review of "the product" - giving the seller 5 stars overall. In the end, I have a 60Ah 'LFP' battery, brand new and shipped to my door for only $276 (which including a fee for using a USA charge card). Just $4.60 per Ah, roughly half the cost of batteries from USA suppliers.

[Casey Freswick]

I have followed Rickst29’s advice for the last 4 months. Order and canceled an order from one lithium supplier. I was informed that my new battery would not arrive until August 2, 2020. We left today for a 7 week trip to CO and MT. Well yesterday at 4 PM the new battery (exact same battery Rickst29 has been evaluating) arrived on our driveway. Needless to say it was a plan coming together that I had not expected. After getting a couple of new wingnut battery terminals I hooked everything up. I do have a couple of questions:

1. My new inverter fans are not running as far as I an tell. will they only run if and when the converter gets hot?

2. The battery monitor I order has yet to come. So I have not up in a monitor. Do I need this? I set my new converter to lithium mode.

3. My battery is a 100 amp, (not a 200). I have a new 60 AMp circuit but have not put it in. Do I need this?

4. The batter came with a 60 amp charger. It is small. THe wires are really small compared to the new wiring I put in. Should I use this as a back up or should I use my old battery charger which has a 50 AMP super charge option? I am assuming my new converter should be my main “charger”.

5. The battery has a charge meter on the battery, but shouldn’t the battery meter in the TM work for this purpose?

Just a few questions I have as I start our trip.

Thanks.

[rickst29]

Originally Posted by Casey Freswick

I have followed Rickst29’s advice for the last 4 months. Order and canceled an order from one lithium supplier. I was informed that my new battery would not arrive until August 2, 2020. We left today for a 7 week trip to CO and MT. Well yesterday at 4 PM the new battery (exact same battery Rickst29 has been evaluating) arrived on our driveway.

If it looks exactly the same as my photo, then it's probably 60Ah (and not 100Ah). DO NOT confirm "received OK" on your DHGate order, until measuring capacity. You need a coulomb counter meter to do that. You can open a 'request partial refund' up to about 90 days after receipt. I've now got a spare meter, do you want it?

As it happens, you hooked in the new battery before I did! I'm only 1/2 done, started about 2PM with cutting cables and hammering/soldering a few ring-type terminals. The coulomb counter shunt needs ring terminals, do you already have suitable hammer tool to make them tight?

Originally Posted by Casey Freswick

1. My new inverter fans are not running as far as I an tell. will they only run if and when the converter gets hot?

2. The battery monitor I order has yet to come. So I have not up in a monitor. Do I need this? I set my new converter to lithium mode.

3. My battery is a 100 amp, (not a 200). I have a new 60 AMp circuit but have not put it in. Do I need this?

4. The batter came with a 60 amp charger. It is small. THe wires are really small compared to the new wiring I put in. Should I use this as a back up or should I use my old battery charger which has a 50 AMP super charge option? I am assuming my new converter should be my main “charger”.

5. The battery has a charge meter on the battery, but shouldn’t the battery meter in the TM work for this purpose?

Answer 1: Fans should only go active when the Inverter experiences load on the 120V outlets.

Answer 2: You battery is labeled 100Ah. It's probably only 60Ah, and might struggle to deliver more than 60A of current. Go easy on the Inverter - no microwave, no hair electric dryers. (Just toothbrush and cell phone chargers and light loads like a cordered electric drill.) If it's 60Ah, like mine then the total price should be refunded down to about $276. But don't ask until you have measured.

Answer 3: I don't know what you mean by a new '60A circuit', unless you mean from the Converter/Load Center over to the battery. The new Converter can put out over 60A current, and the battery can almost certainly take it all - so a 10-AWG wire with a 30A fuse is not going to handle it. #6, or even #4. Fuse at 80 Amps - not exactly right for continuous loads, but it will be effective to allow 65A and also trip on any short circuit fault. (60A is not enough, and they don't make 70A.)

Answer 4: My battery came with a 120V charger labeled "output 10A, 14.6V". It is 14.6V. It is less than 10A, barely 4.5A. You don't need this on the road, where you can pplug in the Progressive Dynamics Converter - and it's only good to "top off" at home *if* you have a 12V external connector to the battery (with a fuse, of course). I have an external 10-AWG waterproof connector, fused at 30A, which I can use with one of these cheap 120VAC -> 14.6VDC chargers to "top things off" - or (more frequently) I use the port to run a 12V tire air pump.

Answer 5: That is NOT a "charge" meter, that is a volt meter. Compared to my good one, it seems accurate (to the nearest 10th). It is no different than any other volt meter attached to the TM. You cannot tell the 'State of Charge' in these batteries by looking at voltage, unless voltage under test (or small discharge current) is either above 13.3V or below 12.0V. 13.3V is a fully charged battery, and 12.0 is just 10% left. For nearly all of the battery's range of charge states, 20% up to 80%, it will read just a bit more than 12.8 Volts. The Volt meter is only useful for the extremes, you must look at the 'Coulomb Counter' to assess the battery within the larger 'middle zone'.

[rickst29]

I didn't take a photo, because there is really nothing new to see. The microwave now works correctly. (It used to hit the over-current BMS "Battery Management System" limit after about 30 seconds of drawing slightly over 100A -- it's a BIG microwave.) With two batteries, it stays under the BMS current limits of both batteries all the time. Still, I'm not planning to use it for more than 10 minutes at a time! It's a big load on the batteries, and runs them down pretty fast. Things like household '120v' vacuum cleaners draw a lot less current, and I just used the house vac for cleaning the TM - with no plugin.

The battery monitor measures in front of the pair, and they're interconnected one-to-the-other in parallel.
- - - - -
This will be handy in Yosemite coming up in 3 weeks. (3-day boondock up in Tulomne Meadows. I sucessfuly snatched one of the 9 trailer-sized campsites on 'reservation day'. I suppose that the other 8 were all gone by 7:01 AM. ) I'll be bringing lots of DEET, because the bugs are pretty aggressive up there.

[rickst29]

The tiny +12v "power supply" wire (into the small green shunt terminal) can connect to any unswitched 12V power source, it doesn't need to be right at the battery.

Their picture is a bit weird, showing the monitor without a pigtail. There is a pigtail on the monitor, and the longer cable goes into the pigtail (not the back of the monitor).

You can only set a value for total amp-hours (which equals 100% charged). You can't separately change the percentage-of-capacity which that means. So, if your battery isn't fully charged - you put in "60 Ah" (or whatever) out of 100 Ah true capacity as a temporary figure, and the percent-charged will go above 100% as you charge it. The change in Amp-Hours will be a true value. Reset the "total amp hours" to a more useful value near your actual capacity when you have reached reach nearly-full charge on your batteries.

This monitor measures power according to the "-" return current, times the value of "12v" input power voltage.

The label "P-" coresponds to grounding return current (into the batteries) from the entire TM - all loads combined with all charger "-" grounding wires. In a normal TM, most of that current comes from a single large white wire. The big wires on the shunt are the lug for "P -" and "Battery -". All charge current (from solar chargers, the power converter) and all discharge current (from inverters and TM 12v appliances) needs to go through the shunt on both wires. Multiple batteries need to have "battery -" connected together AFTER connecting the shunt "Battery -" to the first battery.

[simonen]

Originally Posted by rickst29

And so, the notion of using #10 wire (30A) or even #8 wire (40A @ 60 degrees C) goes out the window. #6 will be required to do the job, for both "12V" positive and the grounding "-" return. Surprisingly, the Charge current was higher than advertised - about 65A.

I just assembled 1 of 2 (200Ah) LiFePO4 batteries, and charging with WildKat converter is at 54A max so far. I suppose the BMS could be limiting it, but the advertised max continuous amps is 60. I have them connected together with a 1 foot cable.

Another observation is that the DC wires on the converter are getting pretty hot, I am surprised to see they are using 10 gauge wire for those. I think the stock WFCO 55amp converter has thicker wire.

[rickst29]

Originally Posted by simonen

I just assembled 1 of 2 (200Ah) LiFePO4 batteries, and charging with WildKat converter is at 54A max so far. I suppose the BMS could be limiting it, but the advertised max continuous amps is 60. I have them connected together with a 1 foot cable.

Another observation is that the DC wires on the converter are getting pretty hot, I am surprised to see they are using 10 gauge wire for those. I think the stock WFCO 55amp converter has thicker wire.

Since you are using the same 'WildKat' which I own, I'm inclined to blame the BMS clamping down a bit too early. I have a pair of batteries, with total BMS charge current limits quite a bit higher than yours (mine are 50A+50A).
- - - -
For heat, here is my SWAG (I didn't notice a lot of it.) In my own installation, the WildKat "DC out" wires connect into a pair of big brass "DC Distribution Bus" components (they're usually sold as "DC Grounding Bus" for legal reasons, but insulated ones also do a great job with the 12V connections). The kind used in high-end car audio with big amplifiers. The WildKat wires are clamped in really tight, and each bus has some other, larger copper wires attached equally tight:

The grounding bus has the two original #8 TM grounding wires removed from the WFCO grounding lugs and placed on the distribution bus instead. (Those are the ones which connect to the frame behind the plumbing drains) Two additional wires go back to each of the WFCO lugs, and the white WildKat DC "Grounding" output constitutes the 5th wire. That makes up a lot of tightly-connected copper wire length to help dissipate heat from the thin copper of the WildKat DC "grounding" wire. Insulation is thin, on all of these wires.

I do not have a separate "grounding wire" to reach the batteries, and your single much shorter wire might not be as helpful for dissipating heat (as my big set of longer slightly smaller wires: Eespecially the dual #8 to the frame, each about 4 feet long - with the big brass lug connecting them all.

On the +12v bus, I have only a #8 into the DC circuit board, along with the #6 running to my battery pair. But, if you didn't use a strong wire clamping device like my bus, your thermal connection (one the one-foot "test" setup) might not be very good, and your "+12v" wire (actually more like 14.6-14.7v) is very short. In my 2619, the #6 AWG is very, very long, about 24 feet before reaching the batteries - and the first few inches, before the hole in the floor to reach the flex conduit, is not insulated by the liquidtite.
- - -
Maybe you'll get more current with two batteries. Are you using a screw-down bus connector, or just a pair of blue wire nuts?

[simonen]

Thanks for the feedback!

For the moment, this particular test setup is completely on the bench. I have the wildkat converter hooked directly to the BMS/Battery using terminal lugs.

I am performing the initial balance and SOC. Once finished, I will perform the capacity test to determine if they are indeed 200Ah as advertised.

Hopefully this weekend, I will start to move the converter and battery into the trailer. I have already pre-run the #6 battery wire from the WFCO panel to were the battery will go in the storage area by the furnace.

I was just surprised how warm the wildkat wires got during the initial charge, and it was across the whole length of the wires on the charger only. And the Amp reading was simply off the BMS, I didn't put a clamp meter on the wires to get another data point.

Edit (10/30/2020)
- The battery tested out at 200Ah, but I know it would have been more since it decreased the high voltage cutoff and increased the low voltage cutoff.

In case anyone is interested, I got these on Aliexpress from a US shipper. They arrived in 3 days.
https://www.aliexpress.com/item/4001...60a94c4dpBIe3b

The other one I have coming is on a boat from China and takes about 45 days, but it is $200 cheaper (and no tax).

These are double the capacity of a Battleborn for less.

[rickst29]

Originally Posted by simonen

Edit (10/30/2020)
- The battery tested out at 200Ah, but I know it would have been more since it decreased the high voltage cutoff and increased the low voltage cutoff.

In case anyone is interested, I got these on Aliexpress from a US shipper. They arrived in 3 days.
https://www.aliexpress.com/item/4001...60a94c4dpBIe3b

The other one I have coming is on a boat from China and takes about 45 days, but it is $200 cheaper (and no tax).

These are double the capacity of a Battleborn for less.

They look like CATL prismatic clones, and those CATL cells are wonderful. I'm jealous!