Lithium battery upgrade questions

[oldwave]

Originally Posted by Brian B-P

Yes - a microwave oven only needs a 15 amp circuit. Of course you can't run much else at the same time with only 20 amps, but that may not be a problem.

Thank you, that’s what I thought, especially with the small microwave that escape installed in 2017.

[gbaglo]

When it comes to electric, I know nothing, or less than nothing.

[richm]

For Lithium batteries, there are additional advantages to the settings allowed by the Xantrex Freedom XC. One can set the absorption and float voltages anywhere between 12V and 18V.

To extend the life of lithium batteries, I personally plan to program use only the 20% to 90% range of battery capacity. The reason is, this can extending the life, sometimes by and additional 50%. But more importantly, the capacity of the battery will degrade more slowly over time, so you have more capacity when it's a year old, or two years old.

In terms of voltage for typical lithium cells, that may be 90% at 13.3V and 20% at 12.9V. This is sometimes called 'de-rating' the battery, for example de-rating from 100Ah to 70Ah. Just be aware that the 'sweet spot' in terms of durable power capacity may be a relatively small voltage range: just 0.4V.

There is still a scenario when you would charge it up to the full 14.4V or event 14.6V, and that is, to balance all of the individual cells in the battery. This is called 'top balancing'. But that's not required every time the battery is charged. Even without top balancing, any good BMS (Battery Management System in the battery itself) will balance the cells to some degree even when charging to only 13.3V.

I figure if 3000 cycles might be ten years of daily cycling, then limiting the voltage range (as well as the maximum current) may help a lot in terms of having more power capacity in later years.

[rubicon327]

Originally Posted by oldwave

Got it, but the WFCO only allows 20 amp branch circuits. So I am confused by the 30 amp branch circuits and transfer switch. Is this a problem or not ?

I originally questioned this as well so I understand your concern. I recently spoke to an electrician who said a branch breaker sized the same as a main breaker isn't a problem and I don't believe it violates any code. I do understand that WFCO says max 20A branch breakers but I wish they had a better explanation when NewYorkHillBilly inquired with their technical support. The stab bar that the breakers engage with is uniform throughout so I can't even see an argument about individual stab loads being an issue (sometimes on bigger panels the branch breaker socket has an amperage limitation). Not to justify a potentially less-than-ideal design but I can say there are many instances where this is being done beyond just Escapes. Even WFCO's 50A power center models have the same 20A branch breaker limitation. Ultimately you have to do what you are comfortable with.

[oldwave]

Originally Posted by rubicon327

I originally questioned this as well so I understand your concern. I recently spoke to an electrician who said a branch breaker sized the same as a main breaker isn't a problem and I don't believe it violates any code. I do understand that WFCO says max 20A branch breakers but I wish they had a better explanation when NewYorkHillBilly inquired with their technical support. The stab bar that the breakers engage with is uniform throughout so I can't even see an argument about individual stab loads being an issue (sometimes on bigger panels the branch breaker socket has an amperage limitation). Not to justify a potentially less-than-ideal design but I can say there are many instances where this is being done beyond just Escapes. Even WFCO's 50A power center models have the same 20A branch breaker limitation. Ultimately you have to do what you are comfortable with.

Ok thanks, that’s the best explanation if heard, I appreciate the advice.

[oldwave]

I have one other question with our stock interstate flooded batteries, escape generally installs a 1500 watt inverter. Will these batteries power an 1800 or even a 2000 watt inverter? I’m looking at the Progressive dynamics inverters. Not quite ready to go to Lithium yet.

[rubicon327]

Mounted the Xantrex Freedom controller and Victron BMV-712 battery monitor. These are at eye level right over the sink for easy reading / adjustments. Still have to route the comm wiring to both but I did investigate and found a way across the door. Figured out how I will mount the Xantrex inverter/charger. Able to leverage some of the existing wood framing for the dinette seat and added another vertical piece. Very secure and saves space on its side. Cardboard cutout represents the footprint of the Bestgo 400AH lithium battery. For those looking close and see the unsecured wire going into the electric heater I did add a strain relief since I received them from Grainger today. I also added a couple to the back of the WFCO power center because Escape used some plastic pieces that are glued on and just break off if wire is pulled. This is very tough because you need to pull the wires out and thread them through the strain relief and then reconnect. I also dug into the metal junction box that was used inside early trailers (drivers side) for 7-pin connections and it was a bit of a rats nest. Added a new box with color-coded studs (like Escape uses now) and ran a new umbilical out to the tongue. This now sets me up to make my connections and figure out the mounting for the new Victron DC-DC charger and with the cleaner layout it will aid any troubleshooting in the future.

Unfortunately my lithium battery that was due in port 5/17 has been delayed until 5/29. Ideally I’d have it in place before I work on all the 4/0 DC wiring which also includes the Victron shunt, 250A fuse and disconnect switch but I may forge ahead as best as I can and start testing everything on a 12V or dual 6V batteries. More to come...

[rubicon327]

...and to think I’m going to try to get out camping with the kids this weekend!

[Centex]

Originally Posted by rubicon327

[Work in progress]...and to think I’m going to try to get out camping with the kids this weekend!

Lol, BTDT, you'll make it, ya'll have a great weekend!

Thanks so much for the progress reports and pics, Dave, your sharing of modifications experience is always very informative and greatly appreciated. This one is looking good as is typical of your projects!

[rubicon327]

Originally Posted by Centex

Lol, BTDT, you'll make it, ya'll have a great weekend!

Thanks so much for the progress reports and pics, Dave, your sharing of modifications experience is always very informative and greatly appreciated. This one is looking good as is typical of your projects!

Thanks Alan. Getting close to the point where I really need the battery so might be time for a break anyhow. I’m getting nervous because I have 2-3 weeks more after it hits the mainland and I really want it installed and well tested before a June 23rd trip to Assateague.

[cpaharley2008]

Being from Maryland I can state the flies on Assatteague will eat you alive if allowed........

[rubicon327]

Originally Posted by cpaharley2008

Being from Maryland I can state the flies on Assatteague will eat you alive if allowed........

I heard the mosquitos can be bad too. I'll have bug spray, a Clam enclosure and probably pick up a Thermacell mosquito repellent device. Any other suggestions?

[cpaharley2008]

Wait til winter.........

[rubicon327]

Originally Posted by cpaharley2008

Wait til winter.........

Besides that Jim!

[rubicon327]

Originally Posted by richm

For Lithium batteries, there are additional advantages to the settings allowed by the Xantrex Freedom XC. One can set the absorption and float voltages anywhere between 12V and 18V.

To extend the life of lithium batteries, I personally plan to program use only the 20% to 90% range of battery capacity. The reason is, this can extending the life, sometimes by and additional 50%. But more importantly, the capacity of the battery will degrade more slowly over time, so you have more capacity when it's a year old, or two years old.

In terms of voltage for typical lithium cells, that may be 90% at 13.3V and 20% at 12.9V. This is sometimes called 'de-rating' the battery, for example de-rating from 100Ah to 70Ah. Just be aware that the 'sweet spot' in terms of durable power capacity may be a relatively small voltage range: just 0.4V.

There is still a scenario when you would charge it up to the full 14.4V or event 14.6V, and that is, to balance all of the individual cells in the battery. This is called 'top balancing'. But that's not required every time the battery is charged. Even without top balancing, any good BMS (Battery Management System in the battery itself) will balance the cells to some degree even when charging to only 13.3V.

I figure if 3000 cycles might be ten years of daily cycling, then limiting the voltage range (as well as the maximum current) may help a lot in terms of having more power capacity in later years.

Rich: Your point is well taken. Semievolved who tested the 400AH Bestgo lithium battery provided the following when he performed his own test on the battery at a 10A discharge which is inline with what you have said above...
"Bottom line is that this battery produces almost 5.6 kWh of capacity over a usable, safe range. That's a heck of a lot of capacity. For slow charge rates (<0.05C or under 20A), I'd recommend terminating the charge at 14V, which should increase the life cycles of the battery. Likewise, terminating the discharge at 12.4V or at most down to 12.2V will provide assurance that cells are protected from over discharge. Using these high and low cutoffs will still net at least 95% of the maximum capacity according to my test, more than 410Ah for my battery."

[Centex]

While waiting for Dave's install report to continue, I'm pulling this recent post from another thread and sharing my ECPC anecdote just FYI.

Originally Posted by richm

Will Prouse has a video of a disassembled Bestgo 400Ah lithium battery, and said nice things about the build quality.

https://youtu.be/F2ynIbGsc1E

The 12V version is here: https://www.electriccarpartscompany....-battery-packs

Thanks, Rich, for posting the YouTube link (new to me). Personally I have to take a large dose of salt when I watch Mr. Prouse but the peek inside the BestGo is interesting and encouraging.
______
My ECPC anecdote (positive experience) ...

Until about two weeks ago ECPC offered the linked BestGo 12V/400Ah battery at $1930 delivered direct to CONUS residential addresses from China with estimated 8 week delivery time. A good deal for those not in a hurry, the US inventory price being $350 higher with shipping on top of that. On Sunday 05/23/2021 I ordered one online for delivery from China (as did Dave a while back) and received an automated email 'order confirmation' within minutes.

The following Tuesday I received a telephone call from ECPC advising me that the lower-price 'direct from China' option was being removed from the website due to a shipping problem in China (they had just received notification of the problem). In response to that problem ECPC advised my already confirmed order would be filled immediately from their Salt Lake City USA warehouse inventory at the lower already confirmed 'direct from China' price including delivery.

Obviously there's nothing to complain about in ECPC's handling of that unforeseen problem with 'direct from China' shipping, IMO their response was perfectly appropriate and appreciated and I told them that with kudos. BTW, my PayPal was not actually charged until ECPC delivered the shipment to the motor-freight carrier late on Tuesday.

All of this is 'as it should be' but IMO it's reassuring to deal with a business that actually proactively "does the right thing'' and undertakes to keep their customer closely informed when a glitch arises.

My battery is tracking on motor-freight between OKC and Dallas as I type this, might be at the local (Austin) terminal by this Friday, ~6 weeks earlier than I expected when I placed the order.

I can only hope that Dave's battery, ordered well-before the China shipping problem arose and currently in transit, will arrive at this doorstep very soon, too.

[rubicon327]

Originally Posted by Centex

While waiting for Dave's install report to continue, I'm pulling this recent post from another thread and sharing my ECPC anecdote just FYI.
Thanks, Rich, for posting the YouTube link (new to me). Personally I have to take a large dose of salt when I watch Mr. Prouse but the peek inside the BestGo is interesting and encouraging.

Thanks for sharing this. Good to see some optimism about this battery but I agree you have to decipher what is meaningful and what is fluff sometimes in these videos. The capacity test was helpful. In fact semievolved's capacity test data that he shared with me was what convinced me to take the leap. Another good look at the guts of these batteries is available at this link from the ECPC website:
www.electriccarpartscompany.com/assets/images/Preferred%20Battery%20Assembly%20Steps.pdf

Originally Posted by Centex

I can only hope that Dave's battery, ordered well-before the China shipping problem arose and currently in transit, will arrive at this doorstep very soon, too.

ECPC has been top-notch which reflects what I have heard. Whenever I email them they get right back to me. Battery was ordered 4/2. My revised "in port" date was 5/29 but I have not heard anything. The tracking number I was given just says "Shipment information sent to FedEx" with a 4/18 date stamp. Tomorrow will be 9 weeks from order date. I'm not terribly optimistic at this point since I saw a post online last night about someone waiting 4 months to get theirs due to U.S. Customs. This post indicates it was ordered ~Sept 2020 and delivered around the New Year. Looking back I probably would have just paid the extra to get it from ECPC's stock in Utah. I snagged one of these at the original $1930 price + tax but the wait has been tough. This would have run me $2280 + tax + shipping but has an estimated delivery of only 1 week. No rush I guess. I landed at a good stopping point with all systems still fully functional. The good news is I get a break and I don't absolutely need it for the next trip later this month. Although we are off-grid and it would have been a great test.

[richm]

Hey Centex, I plan to install pretty much all of the same components and I'm beginning to think about visualizing the install below the dinette bench.

I hope to get some cabinet dimensions next week and start mocking up the cabinet in some CAD program, maybe freecad. Just wanted to mention the software in case you have some preferences about CAD.

Not that I necessary want perfection, but rather, this could help illustrate where there might be a tight fit or other issues.

[rubicon327]

Originally Posted by rubicon327

ECPC has been top-notch which reflects what I have heard. Whenever I email them they get right back to me. Battery was ordered 4/2. My revised "in port" date was 5/29 but I have not heard anything. The tracking number I was given just says "Shipment information sent to FedEx" with a 4/18 date stamp. Tomorrow will be 9 weeks from order date. I'm not terribly optimistic at this point since I saw a post online last night about someone waiting 4 months to get theirs due to U.S. Customs. This post indicates it was ordered ~Sept 2020 and delivered around the New Year. Looking back I probably would have just paid the extra to get it from ECPC's stock in Utah. I snagged one of these at the original $1930 price + tax but the wait has been tough. This would have run me $2280 + tax + shipping but has an estimated delivery of only 1 week. No rush I guess. I landed at a good stopping point with all systems still fully functional. The good news is I get a break and I don't absolutely need it for the next trip later this month. Although we are off-grid and it would have been a great test.

Bestgo 400 AH lithium battery finally arrived on 6/24! One day shy of 12 weeks from date of order. Arrived in perfect condition at about 30% charge. Put it on a 1A trickle charge with a lithium-compatible NOCO maintainer and brought it up to about 60%. They suggest optimal storage is at 40-60%. I like the built-in battery monitor and it will be a good check against the Victron BMV-712 Smart that is installed and awaiting final connections. Hopefully I have some time in the next month or so to finish it all up.

[stephen99]

Originally Posted by rubicon327

Bestgo 400 AH lithium battery finally arrived on 6/24! One day shy of 12 weeks from date of order. Arrived in perfect condition at about 30% charge. Put it on a 1A trickle charge with a lithium-compatible NOCO maintainer and brought it up to about 60%. They suggest optimal storage is at 40-60%. I like the built-in battery monitor and it will be a good check against the Victron BMV-712 Smart that is installed and awaiting final connections. Hopefully I have some time in the next month or so to finish it all up.

OMG, so much power. How much does that beast weigh?