LifePo4 Battery Upgrade - aka. Searching for Mr Goodbattery

[jordanbigel]

So, I'm fishing for ideas on the best LifePo4 12v batteries/BMS for my boat - I'm not looking for "drop-ins" - but, I am NOT interested in doing a complete DIY build (ie. building battery packs from cells). AND, they need to fit my existing 8D battery rack.

I want to purchase two (or maybe three) 12v battery-packs which in total will provide a minimum 600ah capacity. My plan is to install the new batteries this coming June or July, so I have lots of time.

I am upgrading my boat which currently has 3 x 8D AGM batteries mounted in a custom stainless rack. I already have a (new) Victron Multi (12v/3000/120) and a Balmar large case 200amp alternator with a MC-614 regulator (I also have a small 3kw genset). I plan to add a CerboGX/Touch50GX and a Victron BMV-700 (to replace my ancient Link10) as well as new solar panels w/MPPT controllers.

PRIMARY GOALS
1) identify batteries which will fit in my existing battery rack which was designed to hold 3 8D AGM on their sides - the rack has 3 "slots" - so basically a battery which is no larger than 21" x 11" x 10".

2) identify which BMS to use with those batteries

I have been researching batteries made by Lithionics which offer 2 options which appear suitable (ie. they will fit my rack). The first includes a built-in BMS - but is not a "drop-in" - (I am sure all of you know of it already, it has alternator field wire connections and a bluetooth app, and a CanBUS port which presumably will allow it to communicate with the CerboGX.

The second uses an external BMS which would be my preference since the one with the built-in BMS is larger and would need to be on its side, which Lithioncs says is not recommended - the external BMS version would fit on the rack standing up which seems better. I think both versions provide the same capabilities in terms of the BMS.

- GTX12V315A-E2107-CS20 (built in BMS)
https://lithionicsbattery.com/produc...7-gtx-battery/

- GTX12V320A-E2107-DIN-12HK (external BMS)
https://lithionicsbattery.com/produc...hk-gtx-module/

So, with a pair of (either of) these I would have about 630ah - if "money were no object" I would just buy 3 of these and not bother you kind people with my questions.

But they are sooooo expensive!

Is there another option which will allow me to avoid have to modify the battery rack?

At a minimum, I want to end up with a system which can handle all the possible emergency scenarios gracefully (ie. LVC, HVC, over-temp, etc., etc) without blowing things up and melting things. Clearly the Lithionics can meet that goal if set up properly - but is there another option besides DIY battery packs that will cost less?

Thanks in advance for your help!

PS. Yes, I could modify the battery rack to be suitable for a more common size LifePo battery pack, but the cost of that would be literally thousands - I know all the stainless guys in the area and they all charge ridiculous prices. Certainly, if there were an battery option which was low cost enough to justify the cost of rebuilding the rack, I would do it. But I suspect even the most common size, low cost, LifePo batteries plus the cost of the rack rebuild would be more than just buying the Lithionics which fit the existing rack. Thus, I really doubt there is a financial argument in favor of rebuilding the rack.

[AllenRbrts]

I replaced 4 Full River 160ahr batteries with two of the lithionics internal bms batteries 9 months ago. While the rated capacity is the same the useable capacity is nearly triple. Overall I’m happy and would purchase them or perhaps the external bms version again.

[codingparadox]

I put the 48V/100Ah version of these in my boat -- bought 6 of them (30kWh capacity). Great value, great build quality.

https://www.electriccarpartscompany....cks?redirect=1

[alctel]

Originally Posted by codingparadox

I put the 48V/100Ah version of these in my boat -- bought 6 of them (30kWh capacity). Great value, great build quality.

https://www.electriccarpartscompany....cks?redirect=1

These look interesting, I don't suppose you have any pics of the inside?

I'm in the same boat - my old boat I installed a completely DIY situation using a lot of breakers, an Orion BMS, 8 cells in parallel and series, etc etc

Now on my new boat it seems that at least some of that can be simplified which is nice, so looking for decent 12V batteries, ideally using some kind of external BMS (I still don't really trust many internal BMS...)

[HighTemp]

I second Lithionics batteries. I went with 6 of their 315 aH units. UL approved, internal BMS, blue tooth, internal heater, on/off switch, easy to use app that gives you more data than you may ever want to look at.

They are a bit pricey compared to some of the others out there, but I think they are worth the additional money.

[codingparadox]

Will Prowse goes into a pretty good teardown and review:

https://www.youtube.com/watch?v=F2ynIbGsc1E

All the data that actually matters to me comes through the Victron system around the batteries, including the smartshunt. I don't particularly care about individual battery performance, nor do I want the power drain and pay for the complexity of bluetooth management per battery. I want a simple battery with a bulletproof BMS and a reasonably weatherproof case, all of which the BestGo pack seems to provide. And I say this as a complete data dork who's busy building out a custom remote boat monitoring solution to someday sell since all the current solutions don't give enough data.

Internal heater is the only question that might push people away from the ECPC units IMO. We intend to never weatherproof the boat, so if it freezes, we have a much bigger problem. But we are liveaboards and keeping the boat warm and full of fresh water that needs to not freeze 24/7. But even in the PNW we still kept heaters on the boat to keep the same condition even before we were ever liveaboards.

[alctel]

Originally Posted by codingparadox

Will Prowse goes into a pretty good teardown and review:

All the data that actually matters to me comes through the Victron system around the batteries, including the smartshunt. I don't particularly care about individual battery performance, nor do I want the power drain and pay for the complexity of bluetooth management per battery. I want a simple battery with a bulletproof BMS and a reasonably weatherproof case, all of which the BestGo pack seems to provide. And I say this as a complete data dork who's busy building out a custom remote boat monitoring solution to someday sell since all the current solutions don't give enough data.

Internal heater is the only question that might push people away from the ECPC units IMO. We intend to never weatherproof the boat, so if it freezes, we have a much bigger problem. But we are liveaboards and keeping the boat warm and full of fresh water that needs to not freeze 24/7. But even in the PNW we still kept heaters on the boat to keep the same condition even before we were ever liveaboards.

I think I am the same as you - I am working on keeping a low-power centralised boat database so I can view historical wind speed, figure out fuel consumption etc etc.

I am going to give that video a watch.

[jordanbigel]

Originally Posted by codingparadox

Will Prowse goes into a pretty good teardown and review:

All the data that actually matters to me comes through the Victron system around the batteries, including the smartshunt. I don't particularly care about individual battery performance, nor do I want the power drain and pay for the complexity of bluetooth management per battery. I want a simple battery with a bulletproof BMS and a reasonably weatherproof case, all of which the BestGo pack seems to provide. And I say this as a complete data dork who's busy building out a custom remote boat monitoring solution to someday sell since all the current solutions don't give enough data.

They definitely look interesting to me - the teardown guy is certainly enthusiastic enough. I like the price and the dimensions. Not sure yet what the pros/cons are vs. Lithionics. Worth a deeper look I think.

[codingparadox]

There are a lot of companies charging a ton of money for the same lithium cells you're getting from China. There's not a lot better way to say it. Basically you're paying for better warranty support with the really expensive packs, but ECPC is a real US company that's been around for many years and back the Bestgo batteries, so I still feel like there's a decent warranty on these. Is it worth it to save 50-100% or more compared to the competitors? I'll take the risk, especially when I have 6 of them in parallel and if one dies I still have 5 that work.

[alctel]

Originally Posted by codingparadox

Will Prowse goes into a pretty good teardown and review:

All the data that actually matters to me comes through the Victron system around the batteries, including the smartshunt. I don't particularly care about individual battery performance, nor do I want the power drain and pay for the complexity of bluetooth management per battery. I want a simple battery with a bulletproof BMS and a reasonably weatherproof case, all of which the BestGo pack seems to provide. And I say this as a complete data dork who's busy building out a custom remote boat monitoring solution to someday sell since all the current solutions don't give enough data.

Internal heater is the only question that might push people away from the ECPC units IMO. We intend to never weatherproof the boat, so if it freezes, we have a much bigger problem. But we are liveaboards and keeping the boat warm and full of fresh water that needs to not freeze 24/7. But even in the PNW we still kept heaters on the boat to keep the same condition even before we were ever liveaboards.

The internals look very well made from that video. Love the thick busbars.

How do you get info out from the batteries? Is it over CANBUS or something else? I watched the video and read the documentation and it just seemed like the shunt sent out simple voltage signals on abnormal readings

[codingparadox]

I don't get any info out of the batteries. I have a Victron SmartShunt that all of the negative leads connect to, and then my house system is on the far side of the shunt, so anything in and out of the batteries goes through the shunt. So it measures overall SOC, and voltage (paralleled voltage).

[jordanbigel]

Originally Posted by alctel

The internals look very well made from that video. Love the thick busbars.

How do you get info out from the batteries? Is it over CANBUS or something else? I watched the video and read the documentation and it just seemed like the shunt sent out simple voltage signals on abnormal readings

Meanwhile, 3 months later, I've finally decided to buy 3 of the BestGo 400ah batteries.

WRT info from the batteries, I have not ordered them yet, but I have studied all of the documentation carefully.

The Pro version of the BestGo provides a cable with 3 connectors. One of them connects to a proprietary BMV which appears similar looking to a Victron BMV7xx.

The second cable is meant to be wired to a heater/chiller device - it provides signals requesting cooling or heating as needed (the trigger temps are in the docs, I can't recall the numbers).

The third cable is most useful, IMO - it provides 3 signal wires which indicate 1) temp too high or low, 2) voltage too high or low, 3) current too high or low. The signal wires are normally open-circuit and go closed circuit to indicate a problem. You can wire these in a variety of ways, but my plan is to parallel them together and use a relay to interrupt ignition wire to voltage regulator. Plus I will wire these signals to the aux input of the Victron Multiplus to shut down inverter.

According to the docs, these signals "fire" before the BMS shuts down the battery, providing exactly the opportunity needed to cut loads/charging before the BMS shuts down, and maybe? even prevent the shutdown.

Obviously this is not the same as having access to the internal BMS, but, I think with these shutoffs wired to protect the alternator/wiring from load dumps, I think it is the next best thing and about half the cost of Lithionics.

See: https://www.electriccarpartscompany....-pack-4-27.pdf

[AndyOz]

Anyone seen/tried these?: https://descket.com/product/12v-200a...y-w-bluetooth/

US$80-94 for 200Ah? In Oz, Renogy lists these for A$1250.

If the price is correct and not a scam, that's cheaper than lead-acid!

[chrisr]

Originally Posted by AndyOz

Anyone seen/tried these?: https://descket.com/product/12v-200a...y-w-bluetooth/

US$80-94 for 200Ah? In Oz, Renogy lists these for A$1250.

If the price is correct and not a scam, that's cheaper than lead-acid!

for some reason i am reminded of the old adage "if something seems too good to be true - it probably is"

cheers,

[Simi 60]

Originally Posted by HighTemp

I second Lithionics batteries. I went with 6 of their 315 aH units. UL approved, internal BMS, blue tooth, internal heater, on/off switch, easy to use app that gives you more data than you may ever want to look at.

They are a bit pricey compared to some of the others out there, but I think they are worth the additional money.

A bit pricey?
You dropped $25 grand?

Just one of their 12v @ 300ah cost more than I spent on 6 X 12v @ 280ah each
(Actually configured as 24v X 3 for 840ah)

https://www.offthegridrvs.com/Lithio...dm-ctrl400.htm