Inverter and battery sizing to power my camper microwave

[LaneW]

So, I am getting all sorts of misinformation on this and hope someone can give me correct scoop.

I am planning to replace my LA battery in my truck camper with two, 100 ah Lithium batts (probably SOK). I also need to install an inverter, really just to run my microwave. It’s a 900 watt MW that draws 1350 w according to the manual. Looking at a couple of 2000 watt pure sine inverters. But I am getting conflicting info, even from the manufacturers, as to whether two 100ah lithiums and a 2000 w inverter will be adequate to run the microwave .

Does anyone have definitive information on this question, or can you point me to a truly reliable source for answers?

Thanks in advance!

[StirCrazy]

mbloof wrote:

StirCrazy wrote:


As for Catl cells, they would be a third choice for me but they use the same outter casing for simular capacities, what you have to look at is the weight

Why not CATL? They are (or were) one of the top 3 suppliers of LFP batteries in the world.

I bought a set a few years ago - works for me.



- Mark0.

CATL and CALB trade off for 2nd and 3rd for me, EVE is concidered the top brand. Now is there realy much difference , probably not but the reason for EVE being number 1 for me is EVE has a new manufacturing line which is improving the quality of there products plus they are doing the anti-counterfiting thing, maybe all the manufacturs will jump on with that one, I hope.

Steve

[LaneW]

OP here. Yeah, I got what i needed. Thanks

[3_tons]

I wonder if the OP got an answer to his question??

3 tons

[mbloof]

StirCrazy wrote:


As for Catl cells, they would be a third choice for me but they use the same outter casing for simular capacities, what you have to look at is the weight

Why not CATL? They are (or were) one of the top 3 suppliers of LFP batteries in the world.

I bought a set a few years ago - works for me.



- Mark0.

[StirCrazy]

mbloof wrote:


Honestly you have to take ANY "reviews" on Amazon with a LARGE PORTION of SALT - %99 of them have no idea what they actually have or how to test/review it!

However, let us talk about Batteries specifically shall we?

How many consumers have AH meters? Programmable power supply? Load testers? Current meters? Even a DVM? (are any of the above even calibrated?)

Lets face it, the average Joe/Jane consumer has nether the expertise or the equipment to properly test/review a battery.

While it MAY be different for LFP batteries, the seemingly endless flood of useless/overrated consumer Lithium replacement batteries from China is what I'm basing my opinion on.

Well then again there is the popular CATL 280AH LFP battery cells which I see listed having anywhere from 240-340AH on Amazon (for the SAME cells).

(keep in mind much like FLA's, (while the number is growing) there are a limited number of Lithium and LFP OEM's in the world.



- Mark0.

Ya you have to read review some have no clue or just say "delivered fast" but I think the big thing to understand is how LiFePO4 chemistry works. New they are typicly rated from 3000-3500 cycles @ 100% discharge, by limiting your usage range say you keep it between say 20% and 80% with the off run to 100% to top balance and keep the usage and charging under 0.5C you could bump that cycle number up to 7000 or higher.

but here is the magic about this chemistry. if you did 800 cycles on a typical GC2 battery it would be done (on average) so wouldnt hold a charge bal bal bal... on a LiFePO4 when you reach the cycle life you still have 80% of the capacity left and the degradation slows down.. so you could have another 3000 to 20000 cycles untill that battery wears out if you treat it nice.. Personaly I think the battery would age out before it would die from cycles.

so alot of these 200 buck 100AH batteries you can buy were built using B grade cells, is that bad, I don't think so as long as you know that.. in my opinion they would still out last a FLA battery and give you more usable capacity for the same price.. the bad thing is they were advertising them as "A" grade and a typical "A" cell will pull more than its rated capacity. now a cell can be clasified as "B" grade for several reasons, a blemish, a barcode that doesnt work, doesnt pull over capacity.. (typicaly a "A" grade 304 eve cell will pull 310AH or higher new) but what lest scrupouls builders were doing was taking used cells which could be classed as "B" but shouldn't and building these batteries out of them. so they may have only had 200 to 2000 cycles on them but you didnt know so you might hit that 80% capacity faster than expected. EVE has cracked down on this by changing how there Bar codes are put on the casing so its not a sticker anymore or ink and on "B" grade batteries there is no bar code at all so places cant sell a "B" battery as a "A"

As for Catl cells, they would be a third choice for me but they use the same outter casing for simular capacities, what you have to look at is the weight

so the Catl
240 is 5.1Kg (+/- 10g) 207 x 173.9 x 71.3mm
the 280Ah is 5.34Kg (+/- 10g) 207 x 174 x 72 mm
302Ah is 5.51Kg (+/- 10g) 207.2 x 174 x 71.65 mm

With Eve which is the only cell I'll buy for DIY builds there is a 4mm hight difference between there 280AH and 304AH and almost a 0.3kg weight difference also

[mbloof]

otrfun wrote:
Well I can see from both of your posts you're the eternal optimist--lol!

If you reread my post, you'll notice I merely expressed an opinion, based on some of my experience building/using/testing several lifepo4s using most of the test equipment you mentioned. I also included the opinions/reviews of Will Prowse and a thousand or more consumers who purchased lifepo4's on Amazon.

I just read your post and it contains *only* your opinion . . . and nothing more.

I might add, it's the general consumer that directly or indirectly determines whether the vast majority of us keep our jobs or not. They ultimately decide what works and what doesn't work, by purchasing, or not purchasing, any given product or service.

Not even the most skilled marketing department and/or talented electrical/mechanical engineer has the power to make the general public purchase something they don't want . . . at least in the good ole USA, where we have the freedom to choose.

I do a lot of shopping on Amazon. While the old tried and true adage "if it sounds to good to be true - it usually is" there surely are some deals to be had however considering just about anyone can sign up for selling on their platform AND the "reviews" there are not gated by people that ACTUALLY purchased (let alone tested) the products most of the reviews are fairly to completely useless. (forgetting of course many companies have been caught 'planting' favorable reviews)

I have dozens of stories I could tell from my years of shopping on that platform. The GOOD news is that getting a return authorization is fairly easy and if a product does not function/perform as advertised it can just be returned for something else that might. 🙂

Thankfully for us consumers there are both folks that DO KNOW how to test things AND countless user forums where people share what they bought/used and what worked for them. 🙂

While no matter how many times a day they call I'm not going to buy a fake 'extended warranty' for my car somebodies wayward marketing is endlessly filling my mailbox with fliers for products have have no need/use or desire for. 🙂


- Mark0.

[otrfun]

mbloof wrote:
Honestly you have to take ANY "reviews" on Amazon with a LARGE PORTION of SALT - %99 of them have no idea what they actually have or how to test/review it!

However, let us talk about Batteries specifically shall we?

How many consumers have AH meters? Programmable power supply? Load testers? Current meters? Even a DVM? (are any of the above even calibrated?)

Lets face it, the average Joe/Jane consumer has nether the expertise or the equipment to properly test/review a battery.

While it MAY be different for LFP batteries, the seemingly endless flood of useless/overrated consumer Lithium replacement batteries from China is what I'm basing my opinion on.

Well then again there is the popular CATL 280AH LFP battery cells which I see listed having anywhere from 240-340AH on Amazon (for the SAME cells).

(keep in mind much like FLA's, (while the number is growing) there are a limited number of Lithium and LFP OEM's in the world.



- Mark0.

Well I can see from both of your posts you're the eternal optimist--lol!

If you reread my post, you'll notice I merely expressed an opinion, based on some of my experience building/using/testing several lifepo4s using most of the test equipment you mentioned. I also included the opinions/reviews of Will Prowse and a thousand or more consumers who purchased lifepo4's on Amazon.

I just read your post and it contains *only* your opinion . . . and nothing more.

I might add, it's the general consumer that directly or indirectly determines whether the vast majority of us keep our jobs or not. They ultimately decide what works and what doesn't work, by purchasing, or not purchasing, any given product or service.

Not even the most skilled marketing department and/or talented electrical/mechanical engineer has the power to make the general public purchase something they don't want . . . at least in the good ole USA, where we have the freedom to choose.

[mbloof]

otrfun wrote:

mbloof wrote:
Its a battery that the cells are likely sourced in China (if not the entire unit). Which means:

- The 3 items of interest (cost, AH and cycles) are lied about.

Many/most 'offbrand' and even 'brandnameish' producers will often inflate the AH and/or the cycles using much less expensive cells to achieve a much less expensive price point for their products. (the same could be said of Solar panels where I've seen 40W panels being advertised as 400W!!)

- Due to the large ramp up in EV's LFP batteries (and factories) is on the rise.

The market is being flooded with products however questionable many of those products actual performance might be.

A quick look at even Amazon the price for 100AH of LFP is all over the map!

. . .

- Mark0.

Will Prowse has tested and torn-down scores of no-name, cheap lifepo4 batteries over the years. The vast majority have met ah specs. Actually I've yet to see him test one that hasn't met ah specs; but, odds are I may have missed one or two of his reviews where they didn't.

Even more telling than WP's reviews, are the reviews on cheap, inexpensive, no-name lifepo4 batteries on Amazon. Some of these batteries have hundreds, if not a thousand plus reviews, and still maintain an overall 4.5+ review rating (out of a possible 5). I was hard-pressed to find any overall ratings less than 4.2 or so. Since Amazon is arguably the largest single source for lifepo4 batteries in the US, this indicates to me there are no rampant quality control problems in the lifepo4 marketplace.

As for cycle life, no doubt some lifepo4 batteries use questionable cells. New cells are typically rated for at least 2000 cycles. Even a "used" cell, with say, 500 cycles remaining, should still net the average user at least 5 years of use.

IMO, a long as one uses the same due diligence as you would for any other purchase (read reviews, purchase from a reputable source, etc.), the odds of purchasing a "bad" lifepo4 battery are very low.

Honestly you have to take ANY "reviews" on Amazon with a LARGE PORTION of SALT - %99 of them have no idea what they actually have or how to test/review it!

However, let us talk about Batteries specifically shall we?

How many consumers have AH meters? Programmable power supply? Load testers? Current meters? Even a DVM? (are any of the above even calibrated?)

Lets face it, the average Joe/Jane consumer has nether the expertise or the equipment to properly test/review a battery.

While it MAY be different for LFP batteries, the seemingly endless flood of useless/overrated consumer Lithium replacement batteries from China is what I'm basing my opinion on.

Well then again there is the popular CATL 280AH LFP battery cells which I see listed having anywhere from 240-340AH on Amazon (for the SAME cells).

(keep in mind much like FLA's, (while the number is growing) there are a limited number of Lithium and LFP OEM's in the world.



- Mark0.

[otrfun]

mbloof wrote:
Its a battery that the cells are likely sourced in China (if not the entire unit). Which means:

- The 3 items of interest (cost, AH and cycles) are lied about.

Many/most 'offbrand' and even 'brandnameish' producers will often inflate the AH and/or the cycles using much less expensive cells to achieve a much less expensive price point for their products. (the same could be said of Solar panels where I've seen 40W panels being advertised as 400W!!)

- Due to the large ramp up in EV's LFP batteries (and factories) is on the rise.

The market is being flooded with products however questionable many of those products actual performance might be.

A quick look at even Amazon the price for 100AH of LFP is all over the map!

. . .

- Mark0.

Will Prowse has tested and torn-down scores of no-name, cheap lifepo4 batteries over the years. The vast majority have met ah specs. Actually I've yet to see him test one that hasn't met ah specs; but, odds are I may have missed one or two of his reviews where they didn't.

Even more telling than WP's reviews, are the reviews on cheap, inexpensive, no-name lifepo4 batteries on Amazon. Some of these batteries have hundreds, if not a thousand plus reviews, and still maintain an overall 4.5+ review rating (out of a possible 5). I was hard-pressed to find any overall ratings less than 4.2 or so. Since Amazon is arguably the largest single source for lifepo4 batteries in the US, this indicates to me there are no rampant quality control problems in the lifepo4 marketplace.

As for cycle life, no doubt some lifepo4 batteries use questionable cells. New cells are typically rated for at least 2000 cycles. Even a "used" cell, with say, 500 cycles remaining, should still net the average user at least 5 years of use.

IMO, a long as one uses the same due diligence as you would for any other purchase (read reviews, purchase from a reputable source, etc.), the odds of purchasing a "bad" lifepo4 battery are very low.

[otrfun]

StirCrazy wrote:
not better, Ill try streamline my paragraph. prismatic cells are not "cheeper" or "lower quality" the reason for the higher cost involved in say battle born is the increased labour costs to assemble the batteries and the fact they havent realy keept up to the dropping LFP prices as they nave a nich market and do a good sales job of making people think they are vastly superior to other batteries.

Battle born is a parallel/series battery where my battery is a series arangment, and in my 5th wheel I am building a series/parrallel setup , and yes if one cell goes bad in a prismatic you will notice it more, but at the same time it would take me about 5 min to replace the cell with a new one, I would be a few hours to try fix a battle born and need a lot more specialized tools

in the battle born they use 120 1AH cells to make there 100AH battery so they basicly have 30 parralel lines, so if you lose one series line, you lose 1/30th of the battery capacity so yes in that way you have more built in redundency but I was talking about the chance of there being a problem with the battery not the effect. if you notice you lost a cell are you going to sent it in for repair? well that depends I don't think the adverage person would even notice it and run a defective battery for ever. hopefully they have the BMS set up to let you know if there is an issue as that is capable of knowing right away.

does this make battle born better, maybe if your talking redundency, but I still don't think that redundency is worth the price there asking, the battle born by this time should be about 700 bucks concidering you can get thoes 120 cells for under 200 bucks.

I have been looking at them laitly and trying to decide weather to build a prismatic for the 5th wheel or try build out of cilendrical cells. its a lot cheeper for me to buy the clindrical cells, and I cam print specilized holders with my 3D printer, but I would have to buy something to spot weld them togeather and figure that out.

Thanks for taking the time to focus on cell arrangement, Steve.

Based on the two following quotes from your post (in bold italics), I believe you somewhat agree with my premise a 100ah Battleborn (BB) battery with the 120 cell, parallel/series cell arrangement is more reliable, has more redundancy than a 100ah battery with 4 in-series prismatic cells:

1. If a 100ah BB battery experiences a bad cell "you lose 1/30th of the battery capacity so yes in that way you have more built in redundency".

2. If you're using a 100ah lifepo4 battery with 4 in-series prismatic cells "yes if one cell goes bad in a prismatic you will notice it more. Agree. However, let's put your comment into complete perspective. If one cell is truly bad, has no output, the *entire* battery will cease to operate or produce any output.

From my perspective, this represents a big difference in redundancy no matter how you dice it. A 100ah BB can sustain a number of bad cells and continue to work satisfactorily. A 4 in-series prismatic cell battery could potentially have no output with just one bad cell.

Yes, there are other factors that play into the reliability of any given lifepo4 battery, but my discussion is only focusing only cell arrangement.

As for whether Battleborn batteries are worth their premium price, well their value (or lack of) is solely in the eyes of the beholder. Probably the easiest comparison to make here involves automotive tools. There are Snap-On tools and there are Harbor Freight tools. Each has their rightful place in the marketplace, just like Battleborn and other lifepo4 battery manufacturers do. There's no one best tool or battery for everyone.

The "best" battery for us has been the DIY 200ah lifepo4 battery we built almost 2 years ago. Cheap, small, light, reliable and safely operates at .3c charge/.6c discharge in ambient temps down to -10f. As I've mentioned a number of times before, one of our best upgrades ever---a game-changer.

[mbloof]

Its a battery that the cells are likely sourced in China (if not the entire unit). Which means:

- The 3 items of interest (cost, AH and cycles) are lied about.

Many/most 'offbrand' and even 'brandnameish' producers will often inflate the AH and/or the cycles using much less expensive cells to achieve a much less expensive price point for their products. (the same could be said of Solar panels where I've seen 40W panels being advertised as 400W!!)

- Due to the large ramp up in EV's LFP batteries (and factories) is on the rise.

The market is being flooded with products however questionable many of those products actual performance might be.

A quick look at even Amazon the price for 100AH of LFP is all over the map!

Sure while a set of 4 CATL LFP 280AH cells run ~$700 on Amazon, add a BMS and some busbars for less than a Battleborn many want the 'off the shelf' finished product.


- Mark0.

[2oldman]

Cheaper, not cheeper.. among others.

[StirCrazy]

otrfun wrote:

StirCrazy wrote:

otrfun wrote:

StirCrazy wrote:
. . . I would argue there is more potential for something to go wring in a battle born with over 100 cells soldered in as aposed to a prismatic type with only 8 battery conections, but it will be easier to detect on the prismatic . . .

I would argue there is less potential.

The 100ah Battleborn (BB) battery cost more for a very good reason---better redundancy. BB uses 100+ cylindrical cells spot-welded in a parallel/series configuration (vs. series connected prismatic cells). Configured this way, a few cells can loose capacity or become unbalanced and have very little effect on the battery's overall output.

99% of the 100ah lifepo4 batteries on Amazon, etc., use prismatic cells. Typically 4 in series. If *any* of these 4 cells loose capacity or become unbalanced it directly and immediately degrades the overall output of the battery---potentially to the point the battery becomes almost unusable, all because of one cell.

BB could have easily chosen to use less expensive prismatic cells, but they didn't in order to provide a more stable, robust battery.

your talking about the noticable effect not the potential, and I did say that I believe. in a battle born if a solder joint comes lose it or a cell goes bad depending where it is you might not realy notice it or you may notice it a fair bit depending on the failur. in a prismatic if one goes bad you know it, which I concider a good thing and ease of changing out a cell in a prismatic system is by far more easy. I would argue also that prismatic may or may not be less expensive. the actual physical cell the celindrical cell is much cheper to produce on automated lines so to buy the cells them self the 120 cells in a 100AH battle born are cheeper than four 100AH prismatic cells untill recently.... the manufactuing process for prismatic has been altered and ramped up which is bring the cost down on prismatic quite significantly. you have less conections inside a prismatic battery so less chance for a factory defect, which also translates for lower labour costs. because you have 12 to 20 conections over 10 posts in a prismatic compared to the 240+ in a celinderical set up so the labour to wire/conect the cells is much less. the new production savings and increase in amounts of prismatic cells is making them more populer in automotive aplication which is bringing the price of automotive battery down. tesla is now doing all there chinese cars with LFP prismatic cells.

Steve

We've been down this road before where I begin to have a difficult time following you.

You're making general statements about various costs, faulty/excessive connections, manufacturing processes, the ease of changing cells, faulty solder connections, popularity, etc. You've made it clear that you feel batteries that use prismatic cells are "better", I get that.

However, my previous post compared the *PARALLEL* and series cell arrangement used in the 100ah BB batteries to the *SERIES* ONLY cell arrangement used in 100ah batteries that use prismatic cells. Unless, you're willing to discuss this in some fashion, then I'm sorry, I have nothing further to add.

not better, Ill try streamline my paragraph. prismatic cells are not "cheeper" or "lower quality" the reason for the higher cost involved in say battle born is the increased labour costs to assemble the batteries and the fact they havent realy keept up to the dropping LFP prices as they nave a nich market and do a good sales job of making people think they are vastly superior to other batteries.

Battle born is a parallel/series battery where my battery is a series arangment, and in my 5th wheel I am building a series/parrallel setup , and yes if one cell goes bad in a prismatic you will notice it more, but at the same time it would take me about 5 min to replace the cell with a new one, I would be a few hours to try fix a battle born and need a lot more specialized tools

in the battle born they use 120 1AH cells to make there 100AH battery so they basicly have 30 parralel lines, so if you lose one series line, you lose 1/30th of the battery capacity so yes in that way you have more built in redundency but I was talking about the chance of there being a problem with the battery not the effect. if you notice you lost a cell are you going to sent it in for repair? well that depends I don't think the adverage person would even notice it and run a defective battery for ever. hopefully they have the BMS set up to let you know if there is an issue as that is capable of knowing right away.

does this make battle born better, maybe if your talking redundency, but I still don't think that redundency is worth the price there asking, the battle born by this time should be about 700 bucks concidering you can get thoes 120 cells for under 200 bucks.

I have been looking at them laitly and trying to decide weather to build a prismatic for the 5th wheel or try build out of cilendrical cells. its a lot cheeper for me to buy the clindrical cells, and I cam print specilized holders with my 3D printer, but I would have to buy something to spot weld them togeather and figure that out.

[otrfun]

StirCrazy wrote:

otrfun wrote:

StirCrazy wrote:
. . . I would argue there is more potential for something to go wring in a battle born with over 100 cells soldered in as aposed to a prismatic type with only 8 battery conections, but it will be easier to detect on the prismatic . . .

I would argue there is less potential.

The 100ah Battleborn (BB) battery cost more for a very good reason---better redundancy. BB uses 100+ cylindrical cells spot-welded in a parallel/series configuration (vs. series connected prismatic cells). Configured this way, a few cells can loose capacity or become unbalanced and have very little effect on the battery's overall output.

99% of the 100ah lifepo4 batteries on Amazon, etc., use prismatic cells. Typically 4 in series. If *any* of these 4 cells loose capacity or become unbalanced it directly and immediately degrades the overall output of the battery---potentially to the point the battery becomes almost unusable, all because of one cell.

BB could have easily chosen to use less expensive prismatic cells, but they didn't in order to provide a more stable, robust battery.

your talking about the noticable effect not the potential, and I did say that I believe. in a battle born if a solder joint comes lose it or a cell goes bad depending where it is you might not realy notice it or you may notice it a fair bit depending on the failur. in a prismatic if one goes bad you know it, which I concider a good thing and ease of changing out a cell in a prismatic system is by far more easy. I would argue also that prismatic may or may not be less expensive. the actual physical cell the celindrical cell is much cheper to produce on automated lines so to buy the cells them self the 120 cells in a 100AH battle born are cheeper than four 100AH prismatic cells untill recently.... the manufactuing process for prismatic has been altered and ramped up which is bring the cost down on prismatic quite significantly. you have less conections inside a prismatic battery so less chance for a factory defect, which also translates for lower labour costs. because you have 12 to 20 conections over 10 posts in a prismatic compared to the 240+ in a celinderical set up so the labour to wire/conect the cells is much less. the new production savings and increase in amounts of prismatic cells is making them more populer in automotive aplication which is bringing the price of automotive battery down. tesla is now doing all there chinese cars with LFP prismatic cells.

Steve

We've been down this road before where I begin to have a difficult time following you.

You're making general statements about various costs, faulty/excessive connections, manufacturing processes, the ease of changing cells, faulty solder connections, popularity, etc. You've made it clear that you feel batteries that use prismatic cells are "better", I get that.

However, my previous post compared the *PARALLEL* and series cell arrangement used in the 100ah BB batteries to the *SERIES* ONLY cell arrangement used in 100ah batteries that use prismatic cells. Unless, you're willing to discuss this in some fashion, then I'm sorry, I have nothing further to add.