Cheap China lifepo batteries

[Scubaseas]

Originally Posted by Nightsky

... You can't just compare published $/Ah. There is much more to the equation, including intangibles like peace and quiet.

Couldn't agree more. But after 30 years using FLA and AGM it's hard to rationalize spending $6K to $8K on LFP when $1K to $2K for an old fashioned bank has worked just fine for me.

I see all the benefits but I doubt I'd outlast the LFP battery bank if it makes it past 10 years. I get the whole turn the boat into a solar farm concept too. And I'd still like to see standards from ABYC before dumping that kind of money into a LFP system.

[Davidhoy]

Originally Posted by Scubaseas

And I'd still like to see standards from ABYC before dumping that kind of money into a LFP system.

ABYC's recommendations were published in document TE-13 in July 2020. Sorry I can't actually share the document, it is proprietary for ABYC members only (a bit crazy, I agree). One key item that I mentioned in my earlier response is the need for monitoring capabilities.

-David

[Scubaseas]

Originally Posted by Davidhoy

ABYC's recommendations were published in document TE-13 in July 2020. Sorry I can't actually share the document, it is proprietary for ABYC members only (a bit crazy, I agree). One key item that I mentioned in my earlier response is the need for monitoring capabilities.

-David

Indeed. I can get the TE13 if I renew my membership and buy the updates. But a Technical Bulletin isn't a Standard. If I put in a LFP bank and go to sell my boat how does the purchaser's C&V surveyor handle that? How does the insurance company handle that survey? Hard to say the battery bank is up to standards or not when there isn't one yet. At least with the higher end stuff like Victron you get communication and UL listings, not so much with cheap prismatic grade b cells and cheapy BMS units. I suppose if I get a system to the technical bulletin that'll probably be fine but I could just wait until ABYC or someone else decides on standards. At least Bureau Veritas has some standards out as pointed out on Marinehowto.com excellent website.

For me personally aside from the sticker shock there seems to be a huge rush to get a LFP as cheap as possible. I'm not convinced the cheapest Chinesium crap you can get on Alibaba is the way to go. This may come back to bite people when they go to sell their boat or if they change insurance companies and require a new survey.

And I do get the whole "I put it in and it works great" school of thought.

[Davidhoy]

Originally Posted by Scubaseas

Indeed. I can get the TE13 if I renew my membership and buy the updates. But a Technical Bulletin isn't a Standard. If I put in a LFP bank and go to sell my boat how does the purchaser's C&V surveyor handle that? How does the insurance company handle that survey? Hard to say the battery bank is up to standards or not when there isn't one yet. At least with the higher end stuff like Victron you get communication and UL listings, not so much with cheap prismatic grade b cells and cheapy BMS units. I suppose if I get a system to the technical bulletin that'll probably be fine but I could just wait until ABYC or someone else decides on standards. At least Bureau Veritas has some standards out as pointed out on Marinehowto.com excellent website.

For me personally aside from the sticker shock there seems to be a huge rush to get a LFP as cheap as possible. I'm not convinced the cheapest Chinesium crap you can get on Alibaba is the way to go. This may come back to bite people when they go to sell their boat or if they change insurance companies and require a new survey.

And I do get the whole "I put it in and it works great" school of thought.

You do realize that the cells in the "higher end stuff" all come from China, right? Probably the same suppliers too. It's the engineering around the cells that makes the difference, at least in my opinion. The interconnects, BMS, settings, communications, etc. Those are the things that really add value, but what I see from the companies that sell the drop-in batteries and systems borders on gouging. For example, a 300Ah Relion RB300 battery is the size of an 8D and costs $3500. A comparable "DIY" system would run you about $500, including the BMS, and be 1/3 of the size and half the weight. $3000 in "markup" is a lot, not matter how you try to slice it.

[Scubaseas]

Originally Posted by Davidhoy

You do realize that the cells in the "higher end stuff" all come from China, right? Probably the same suppliers too. It's the engineering around the cells that makes the difference, at least in my opinion. The interconnects, BMS, settings, communications, etc. Those are the things that really add value, but what I see from the companies that sell the drop-in batteries and systems borders on gouging. For example, a 300Ah Relion RB300 battery is the size of an 8D and costs $3500. A comparable "DIY" system would run you about $500, including the BMS, and be 1/3 of the size and half the weight. $3000 in "markup" is a lot, not matter how you try to slice it.

I agree with you. Yes, thank you I am aware the virtually all cells sold in the US originate in China. I also see cells being touted that don't even have q codes on them. I appreciate Will Prowse cutting open stuff to show what's going on. Some are fine, some not so much.

At least the Relion has a three year warranty. Seems if you want a warranty it's going to cost you. Which may say something all by itself.

Please show me where I can spend $500 that will get me 300AH grade a, new, q coded cells that come from a well known manufacturer like CALB, Winston, Fortune and that has a BMS included in that price that can communicate. And make sure the BMS is around 100 or more amps rated.

[Davidhoy]

Originally Posted by Scubaseas

Please show me where I can spend $500 that will get me 300AH grade a, new, q coded cells that come from a well known manufacturer like CALB, Winston, Fortune and that has a BMS included in that price that can communicate. And make sure the BMS is around 100 or more amps rated.

4x CATL 310Ah 3.2Ah Grade A cells with QR code, $89 each
1x Overkill Solar 4s 120A BMS with Bluetooth, $115 each

CATL is a very reputable, well-established manufacturer, makes a lot of the cells that go into other manufacturer's products. The BMS that Overkill Solar resells is the same unit that many medical battery systems use internally. Yes, you still need to build a system around the 4s battery, but you have to do that with other manufacturer's batteries too. There is no such thing as a "drop in replacement" battery, despite the advertising to the contrary. An inappropriately sized and regulated alternator will die just as quickly with any lithium battery, regardless of who makes it.

[Scubaseas]

Originally Posted by Davidhoy

4x CATL 310Ah 3.2Ah Grade A cells with QR code, $89 each
1x Overkill Solar 4s 120A BMS with Bluetooth, $115 each

CATL is a very reputable, well-established manufacturer, makes a lot of the cells that go into other manufacturer's products. The BMS that Overkill Solar resells is the same unit that many medical battery systems use internally. Yes, you still need to build a system around the 4s battery, but you have to do that with other manufacturer's batteries too. There is no such thing as a "drop in replacement" battery, despite the advertising to the contrary. An inappropriately sized and regulated alternator will die just as quickly with any lithium battery, regardless of who makes it.

I don't doubt that CATL is a firm that makes batteries. I am sure if they are selling through a third party on Aliexpress or Alibaba a product that is 1/3 the price of a cell made by CALB, Sinopoloy, Winston, Fortune or other well known manufacturers that it would be fine. Unbelievably low pricing from a Chinese website is perfectly OK. I'm sure the rest of the market is just price gouging and these are nothing but the real deal. I have never heard of a bait and switch from some small trading Company selling on Alibaba or Aliexpress. Must be true if it's on the Internet. I assume you do not have a set of these cells? I guess the only way to find out is to buy some.

[Davidhoy]

Originally Posted by Scubaseas

I don't doubt that CATL is a firm that makes batteries. I am sure if they are selling through a third party on Aliexpress or Alibaba a product that is 1/3 the price of a cell made by CALB, Sinopoloy, Winston, Fortune or other well known manufacturers that it would be fine. Unbelievably low pricing from a Chinese website is perfectly OK. I'm sure the rest of the market is just price gouging and these are nothing but the real deal. I have never heard of a bait and switch from some small trading Company selling on Alibaba or Aliexpress. Must be true if it's on the Internet. I assume you do not have a set of these cells? I guess the only way to find out is to buy some.

Laugh all you want - who knows, you might even be right. But CATL makes the cells for Tesla, Honda, BMW, Daimler AG, Toyota, Volkswagen, and Volvo. They are the 3rd largest manufacturer of lithium batteries in the world. Yes, they are Chinese. And yes, I do not have them, yet, though they are on order. I wonder who will have the last laugh? Might be you, might be me...

[Scubaseas]

Originally Posted by Davidhoy

Laugh all you want - who knows, you might even be right. But CATL makes the cells for Tesla, Honda, BMW, Daimler AG, Toyota, Volkswagen, and Volvo. They are the 3rd largest manufacturer of lithium batteries in the world. Yes, they are Chinese. And yes, I do not have them, yet, though they are on order. I wonder who will have the last laugh? Might be you, might be me...

I do not doubt CATL makes fine cells and yes I can read the same stuff on the Interweb you can. I question if you are actually buying grade A new CATL cells at that price point and not some other manufacturer that the marketer is calling CATL cells. Something like that would never, ever happen on Alibaba or Aliexpress.

I may be replacing my bank soon and am leaning to LFP from cells. I'd love to buy top of the line prismatic cells at the cheapest price I can find on Alibaba. Let us all know how it turns out for you.

I doubt very much that CATL can manufacture and market cells at 1/3 the price that Winston, Sinopoloy, CALB and others are charging. If they are as advertised great. If they aren't good luck returning them.

[hzcruiser]

Originally Posted by Scubaseas

I do not doubt CATL makes fine cells

Correct, you can always get ripped off when buying from far-away sources like Alibaba vs buying local, where you can take them back after 6 months and complain.
Life's a gamble.

[Franziska]

Hi, have a look at my very recent very long thread on the same subject, tons of info in there.
https://www.cruisersforum.com/forums...-new-post.html

[KenR]

I very rarely post but before you spend a lot of money, make a valid electrical plan. Make sure you consider all error conditions when a BMS disconnects the LiFePo4 batteries especially when one or more chargers including the alternator are working. Consider programmable BMS and chargers so they work together nicely. While there are quality BMS devices currently available, I am looking for a BMS that raises an error condition pending signal so I have means to shutdown chargers before the BMS disconnects; relays are not fast enough. There are other solutions available, buy they are somewhat a kludge. Good luck.

[mitiempo]

Originally Posted by KenR

I very rarely post but before you spend a lot of money, make a valid electrical plan. Make sure you consider all error conditions when a BMS disconnects the LiFePo4 batteries especially when one or more chargers including the alternator are working. Consider programmable BMS and chargers so they work together nicely. While there are quality BMS devices currently available, I am looking for a BMS that raises an error condition pending signal so I have means to shutdown chargers before the BMS disconnects; relays are not fast enough. There are other solutions available, buy they are somewhat a kludge. Good luck.

The Electrodacus BMS doesn't disconnect the battery totally if there is an issue. It shuts off charging if there is an issue but keeps loads on. If you are using an inverter for example and the battery reaches the low cut off voltage it will shut off the inverter but leave charging alone. It is fully programmable.
Current does not flow through the BMS. It controls loads and charge sources through sensing wires.

https://electrodacus.com/

[com5984]

I just got some 48V 200ah batteries from Lithium Valley 1750 usd each. They seem to have a good reputation and were very easy to deal with.
https://www.lithiumvalley.com/

[more]

Originally Posted by KenR

I very rarely post but before you spend a lot of money, make a valid electrical plan. Make sure you consider all error conditions when a BMS disconnects the LiFePo4 batteries especially when one or more chargers including the alternator are working. Consider programmable BMS and chargers so they work together nicely. While there are quality BMS devices currently available, I am looking for a BMS that raises an error condition pending signal so I have means to shutdown chargers before the BMS disconnects; relays are not fast enough. There are other solutions available, buy they are somewhat a kludge. Good luck.

I don't have BMS i have a passive cell balancer 2-5 A
Contrary to popular belief YOU DO NOT NEED A BMS TO TAKE CARE OF LIFEPO4 BATTERIES, however if you do not use a BMS you must monitor your pack manually, the good news here, if your pack is well balanced to begin with you, will only need to check your pack maybe every 20 to 40 charge discharge cycles. Here is how you can do this.
Each cell fully charged should register 3.3v up to 3.65v(danger zone but this is 14,6v inside battery ) charging source must be 16+v
https://endless-sphere.com/forums/vi...harge%20cycles.

Now I use lifepo4 on boat 3 year going in 4 years maybe next winter I put one dally BMS 200 A because the charging side must be 100A +.
my Winston 200 ah cell is day 3,35 V 85-90% in morning 3,3 this is around 70% I be know better this summer because install shunt battery monitor.
more info voltage,soc and similar
https://docs.google.com/spreadsheets...#gid=968848831