Trojan lithium finally here!

[Ampster]

Is that for used CALB or new ones? ....

New ones from the first vendor I hit on.

https://www.electriccarpartscompany.com/200Ah-CALB-SE-Batteries

if you want to look at used Lithium; Tesla 24v 5kW packs are going for $1200 to $1500 from reliable vendors. That is $300 per kWh or less.

[Ampster]

Is that for used CALB or new ones? ....

New ones from the first vendor I hit on.
if you want to look at used Lithium; Tesla 24v 5kW packs are going for $1200 to $1500 from reliable vendors. That is $300 per kWh or less.

[SunEagle]

New ones from the first vendor I hit on.
if you want to look at used Lithium; Tesla 24v 5kW packs are going for $1200 to $1500 from reliable vendors. That is $300 per kWh or less.

Nice. My first look had the CALB rated 180Ah at $260 plus shipping. I guess if I looked I could find them for less.

[Mike90250]

.....I’ve seen too many lead acid batteries destroyed by rapid charging to be interested in an off grid setup that uses over 10kwh per night cycle.

the user needs to size the battery bank and genset properly. There is no reason batteries have to be destructively recharged. A Lead Acid bank called to supply 10kwh nightly, should be about a 50kwh bank,

[tom rickard]

I agree with you Mike, that’s exactly my point. A 50kwh lead acid vs a 15kwh lithium for the same performance..

[PNjunction]

Thing is, most of us DIY'ers are going to murder any good deals we come across with poor infrastructure wiring and the like. Not cleaning the contacts, using the wrong metals for interconnects, the list goes on.

Then again, there's a lot of "drop in" boxes out there that are constructed with similarly poor and even unsafe practices. Nice and shiny on the outside, and on the inside - oh man. There go your LFP savings when all those bad points of failure happen.

There is a fellow on the 'tube that cuts open these expensive LifePo4 "drop in's", and most are truly shocking. I'd have to say that although Battle-Born is out of my budget, their construction technique looks sound for a drop-in. Others - ugh, not so much.

So who will be the first to cut these major-name drop-in's open and take a peek?

[Jman]

These dropins are mainly for boats and RV's where the AH capacity is small and the charge sources BIG. Like 2hrs to fully recharge while motoring on a boat with twin alternators.
I thought you offgrid guys build out of raw prismatic cells? That is what I would do, half the cost and with proper fusing, LV/HV relays, fluke meter, some resistors for top balacning you would have a good setup. Personally I wouldn't touch the trojan stuff. Take a look at the Lithionics....I believe the best dropin you can get using A grade cylindricals that claim 4000cycles at some high rate. Are they A123? i doubt it considering how pricy A123 would be. For me dropins are strickly for recreational use. They all are about making money and there are no standards like what are the cells they use? A grade and well matched? nah just advertise 3000cycles and that is all you need.

[Ampster]

Do you consider SimpliPhi in that same light?

[SunEagle]

These dropins are mainly for boats and RV's where the AH capacity is small and the charge sources BIG. Like 2hrs to fully recharge while motoring on a boat with twin alternators.
I thought you offgrid guys build out of raw prismatic cells? That is what I would do, half the cost and with proper fusing, LV/HV relays, fluke meter, some resistors for top balacning you would have a good setup. Personally I wouldn't touch the trojan stuff. Take a look at the Lithionics....I believe the best dropin you can get using A grade cylindricals that claim 4000cycles at some high rate. Are they A123? i doubt it considering how pricy A123 would be. For me dropins are strickly for recreational use. They all are about making money and there are no standards like what are the cells they use? A grade and well matched? nah just advertise 3000cycles and that is all you need.

With the cost of a manufactured 25 year panel being less than $1/watt it has become very hard to justify a DIY panel with cells due to them actually costing more than $1/watt and not lasting more than a couple of years due to moisture getting into the system.

I would also look closely at any Li chemistry battery. Sure then can get a high cycle rate along with a high DOD but if you look at the initial cost and calculate the actual kWh it will give you then you will probably find it not as cheap as you think.

[Ampster]

With the cost of a manufactured 25 year panel being less than $1/watt it has become very hard to justify a DIY panel with cells due to them actually costing more than $1/watt and not lasting more than a couple of years due to moisture getting into the system.

I would also look closely at any Li chemistry battery. Sure then can get a high cycle rate along with a high DOD but if you look at the initial cost and calculate the actual kWh it will give you then you will probably find it not as cheap as you think.

That is an interesting comparison. Li chemistry has not become commoditized in this niche like it has in EVs and large grid support systems. It is hard to tell when that will happen if at all. Another niche that hangs in there with Lead Acid is golf carts.

[SunEagle]

That is an interesting comparison. Li chemistry has not become commoditized in this niche like it has in EVs and large grid support systems. It is hard to tell when that will happen if at all. Another niche that hangs in there with Lead Acid is golf carts.

I agree that certain battery chemistries have their places. Li in EV's and FLA in golf carts.

All I am saying is that based on the cost of new Li chemistry batteries when I divide the lifetime estimated kWh that they can produce into the cost I get more than $.50/kWh which is way above what it costs me from the POCO.

Now with used Li batteries and higher POCO costs it becomes financially smart to go with battery storage. But that isn't everywhere yet.

[PNjunction]

At this point, I'd like to see a teardown video.

You guys know me, the classic LiFeP04 prismatics and manual monitoring yadda yadda. But enough time has passed that if someone is going to go the drop-in route, it's best not to err on the cheap side.

This excitable fellow does tear-downs of drop-ins. Most are truly awful, but some are quite nice, like Battle Born.

https://www.youtube.com/watch?v=G5E30u-66VI

You'll be shocked at some of the other manufacturer's teardowns he does.

I hate to say it, but at this point I think a quality manufacturer with built-in bms and quality cells will solve some of the most common diy faults that are likely to happen. Not everyone has read through years of threads, or they simply may not have the skills to maintain a totally pieced-together diy bank.

So if that's the case, and LFP is what you need (or think you need), might as well shoot for the highest quality you can. Teardowns will help.

[Ampster]

The interesting thing that has come up in some situations is that these drop in replacements have contactors that can disconnect them to protect them from damage. The problem is that some charge controllers and inverters are not designed for that occurance and that may create issues that have not been anticipated. I can routinely switch off my batteries and my hybrid inverter doesn't care. All I am saying is it adds a new dimension to some systems.

[PNjunction]

The owner makes a point about that for solar users who let the bms go into self-protect, where to a solar system it now appears like there is no battery. So you have to carefully recharge the batt a little separately to get it out of self-protect, and the solar system, seeing a battery voltage, will operate again.

Ie, don't let the bms lvd be the real lvd for solar use. Kind of like not relying on an inverter's lvd be your sole lvd in the lead-acid world.

I'll start a new thread specific to Battle Born because I like what I see.

[Ampster]

The owner makes a point about that for solar users who let the bms go into self-protect, where to a solar system it now appears like there is no battery. So you have to carefully recharge the batt a little separately to get it out of self-protect, and the solar system, seeing a battery voltage, will operate again.

Ie, don't let the bms lvd be the real lvd for solar use. Kind of like not relying on an inverter's lvd be your sole lvd in the lead-acid world.

I'll start a new thread specific to Battle Born because I like what I see.

That is a good point. What I was referring to was something I read that said sometimes to restart a charge controller one has to disconnect the solar and then connect the battery. That means a manual restart. The workaround you suggest would work, but I am not familiar with some charge controllers to know if they even have an LVD.