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Advice on my 280Ah Lifepo4 configuration

Nol

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Hi

I am intent to build my own 12V-280Ah battery for in my RV and found the following parts
Can someone advice me if my configuration is fine ?

Battery pack from Shenshen Basen from Alibaba
120A BMS from Aliexpress
3S-4S 5A balancer from Ebay
Smart battery sense from Ebay
Orion TR Smart 30A from Ebay

Info about the parts :
Someone advice me to buy the 120A BMS because of my 1500W inverter
I think a 5A balancer is better to handle the 280Ah battery instead of a 1,2A version.
I saw the Smart battery sense in a movie from Will and I think it is a good idea to install one
I think I need the Orion TR between the alternator and battery to protect the alternator and battery

I am looking forward for any advice
 
The cells you are looking at are the same basic Commodity cells everyone else sells and have an average price (there is cheaper with delivery DPP).

BMS: I do NOT recognize that brand. Looks like a variation of the ANT BMS. You may rather consider a Heltec BMS with Active Balancer.
The Active Balancer you indicate appears to be by Heltec. Heltec is Known Good for their Active Balancers & BMS'. There are a few threads on here about them with people using them quite happily.
 
Thanks for your reply.

DPP is that the same as DDP which is Delivery Duty Pay ?
Those commodity cells are they good for a 12V RV battery ?

I check the Heltec BMS but the undervoltage protection is at 2,1V which is far to low.
Am I wrong ? Do you have a link to a good one ?
By the way, the BMS which I had in my mind is the same as this ons, maybe this will help
 
BMS: Seems to be fine. There are better options, especially if you want to draw high currents. A 120A BMS will be a little too low for a 1500W inverter (1500W = approx 125A excluding losses and you're likely to run other loads as well in an RV, not just the inverter). However, if you're not maxing out the inverter it will be ok.

I personally however won't run a BMS for a longer period at its max rated current. I'd go for approx 60% max load for longer periods. You can either connect the inverter directly (bypassing the BMS) to the cells, and use a small relay powered by the BMS to switch on/of the inverter (so the BMS will disconnect the relay when a cell reaches its lowest setting, thus shutting down the inverter), or get a bigger BMS.

The BMS is the the same as the JDB, LTT, or OverkillSolar, so not a bad choise if it will fit your needs

For the balancing.. 1.2A or 5A.. If you really need 5A to balance your cells, there is probably something wrong. Especially with lower loads, once balanced properly, if the cells are good and equal, you shouldn't need much balancing, unless a cell is really crap.

Make sure you do a proper top balance before using the battery and you're ready to go. A 1.2A balancer might be handy to do a manual balance when needed, but with good cells you might not need it at all.

For the Orion TR: Good option, but you can look at the Renogy DC-DC charger as well. The 40A version is $199, where as the Victron 30A is $265 or so. (Although Victron is probably slightly higher quality, Victron is generally rated as very good, but I doubt if it makes much sense)
 
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Thanks (again) DJSmiley
Inverter will be no problem, I don´t use it so much and it is always off untill I need it.
That mean that the BMS is fine for what I want.

Will advice in a movies to add an active balancing and he talked about a 1,2A version but that was in combination with 100Ah cells
The intention for a 5A balancing came from MaartenH because of the 280Ah cells which you also have

My load will be the MPPT 75/15 and the altenator passing the Orion TR so total 15 + 30 is 45A
I realy don´t know if 45A is fine or to low
I can check for the Renogy then the total will be 55A
 
Hi

I am intent to build my own 12V-280Ah battery for in my RV and found the following parts
Can someone advice me if my configuration is fine ?

Battery pack from Shenshen Basen from Alibaba
120A BMS from Aliexpress
3S-4S 5A balancer from Ebay
Smart battery sense from Ebay
Orion TR Smart 30A from Ebay

Info about the parts :
Someone advice me to buy the 120A BMS because of my 1500W inverter
I think a 5A balancer is better to handle the 280Ah battery instead of a 1,2A version.
I saw the Smart battery sense in a movie from Will and I think it is a good idea to install one
I think I need the Orion TR between the alternator and battery to protect the alternator and battery

I am looking forward for any advice
Hello, I have been looking at the same set of Batteries, I never order anything from Alibaba before. Did you already place the order? I got burnt from Aliexpress, so I want to make sure I will not have any problem with ordering from Alibaba. When I click on the QTY of 4 it shows $300 for the batteries and $120 but it is not clear if that is the real shipping charge or not, I am from SF BAY area so I want to make sure I will not get shippimg charge surprise, any info you can provide to help me will be great, thanks!
 
Hello, I have been looking at the same set of Batteries, I never order anything from Alibaba before. Did you already place the order? I got burnt from Aliexpress, so I want to make sure I will not have any problem with ordering from Alibaba. When I click on the QTY of 4 it shows $300 for the batteries and $120 but it is not clear if that is the real shipping charge or not, I am from SF BAY area so I want to make sure I will not get shippimg charge surprise, any info you can provide to help me will be great, thanks!

You need to hit the "send enquiry" and ask for a quote.
 
The Heltec parameters are adjustable. You pick lifepo4 as battery type and it fills everything for lifepo4.
Then you can adjust them to whatever you want.
But, the Heltec doesn't work for 4s. :(
The other two BMSs are probably fine.
 
@Bud Martin, no I have not yet order the cells. I am calculate everything so I know what everything cost and if I get everything I need.
I suspect that the shipping cost is what is in the advertise on Alibaba ($126,70 for the US and $129,80 to the Netherlands)
But before I order I send them a message because I also like to know if tax is included (DDP)

@ArthurEld, thanks for confirming that Heltec does not support 4S
Therefor I order the one in my list.

How about the 1,2A or 5A balancer for the 280Ah celles ?
 
@Bud Martin, no I have not yet order the cells. I am calculate everything so I know what everything cost and if I get everything I need.
I suspect that the shipping cost is what is in the advertise on Alibaba ($126,70 for the US and $129,80 to the Netherlands)
But before I order I send them a message because I also like to know if tax is included (DDP)

@ArthurEld, thanks for confirming that Heltec does not support 4S
Therefor I order the one in my list.

How about the 1,2A or 5A balancer for the 280Ah celles ?
I don't have much experience. But you might want to be sure to do a good top balance then just see how the passive balance works that comes with the BMS. If your cells are good you shouldn't need much balancing. No sense having a bunch of wires and crap you don't need.
You can always add it later if you decide you need active balancing.
 
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- Passive Balancing of any form is pretty much useless on cells with capacities above 100AH. 1.2A is too slow and only burns off hi voltage.
- Passive works IF you have properly Matched, Batched & Binned cells with minimal deviation between cells.
- Active Balancing (different methods) tansfers Hi Volts to lo volt cells. Higher amperage = more capability but also more $
- I know of only TWO Known Good Active Balancers, they are Heltec (direct or vendors) & QNBBM brands (sold by DeliGreen). There are several "brands" available but many have been show to be less than what they are advertised to be. There may be more that I am unaware of but I spent a few months researching these prior to purchasing QNBBM's for all of my packs.

HELTEC: https://heltec-bms.com/products/smart-bms/
Deligreen QNBBMs: https://deligreen.en.alibaba.com/productgrouplist-806516208/QNBBM_Balancer.html?

A note about shipping estimates. Ali* sites give an "estimated average" shipping cost on their pages. Most are DPP (Duty & Taxes included). You will get an actual quote once you open a chat with the reps and they get your specific address. For example, one of our Known Good Vendor/Suppliers here Luyuan Tech (Sister company of XUBA) lists prices (bundled deals) with S&H included or without S&H included. They have been shipping cells to our members in Australia to Zambia (literally) and everywhere in between with no issues. There are some places that are slower in receiving but that's due mostly to Covidus Interruptus and staffing issues @ borders.

Link to Luyuan Tech: https://szluyuan.en.alibaba.com/productlist.html?spm=a2700.icbuShop.88.18.1b2048b5wEQqiH

Reading Reference:
Li-Ion BMS - White Paper - Dissipative vs. nondissipative balancing (a.k.a.: Passive vs. Active balancing)
BU-803a: Cell Matching and Balancing – Battery University
 
I think it is not that difficult to explain here ;)
I know what DDP is and DAP, taxes not included but I don´t know what DPP is.
 
OK thanks to explain, then Steve_S make a typo ?
Can happen (y)
 
Hi

I am intent to build my own 12V-280Ah battery for in my RV and found the following parts
Can someone advice me if my configuration is fine ?

Battery pack from Shenshen Basen from Alibaba
120A BMS from Aliexpress
3S-4S 5A balancer from Ebay
Smart battery sense from Ebay
Orion TR Smart 30A from Ebay

Info about the parts :
Someone advice me to buy the 120A BMS because of my 1500W inverter
I think a 5A balancer is better to handle the 280Ah battery instead of a 1,2A version.
I saw the Smart battery sense in a movie from Will and I think it is a good idea to install one
I think I need the Orion TR between the alternator and battery to protect the alternator and battery

I am looking forward for any advice
That looks like a passive balancer.... don't see any switching (like scr or fets). passive bleads your high cells down. active transfer high to low
 
- Passive Balancing of any form is pretty much useless on cells with capacities above 100AH. 1.2A is too slow and only burns off hi voltage.
- Passive works IF you have properly Matched, Batched & Binned cells with minimal deviation between cells.
- Active Balancing (different methods) tansfers Hi Volts to lo volt cells. Higher amperage = more capability but also more $
- I know of only TWO Known Good Active Balancers, they are Heltec (direct or vendors) & QNBBM brands (sold by DeliGreen). There are several "brands" available but many have been show to be less than what they are advertised to be. There may be more that I am unaware of but I spent a few months researching these prior to purchasing QNBBM's for all of my packs.

HELTEC: https://heltec-bms.com/products/smart-bms/
Deligreen QNBBMs: https://deligreen.en.alibaba.com/productgrouplist-806516208/QNBBM_Balancer.html?

A note about shipping estimates. Ali* sites give an "estimated average" shipping cost on their pages. Most are DPP (Duty & Taxes included). You will get an actual quote once you open a chat with the reps and they get your specific address. For example, one of our Known Good Vendor/Suppliers here Luyuan Tech (Sister company of XUBA) lists prices (bundled deals) with S&H included or without S&H included. They have been shipping cells to our members in Australia to Zambia (literally) and everywhere in between with no issues. There are some places that are slower in receiving but that's due mostly to Covidus Interruptus and staffing issues @ borders.

Link to Luyuan Tech: https://szluyuan.en.alibaba.com/productlist.html?spm=a2700.icbuShop.88.18.1b2048b5wEQqiH

Reading Reference:
Li-Ion BMS - White Paper - Dissipative vs. nondissipative balancing (a.k.a.: Passive vs. Active balancing)
BU-803a: Cell Matching and Balancing – Battery University
Steve,

did you by any chance look into the REC active BMS (4S version)? A bit pricey admittedly, but seems to be well built.

There are a number of satisfied users in the marine world.

MP
 
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Like Steve said the ective balancer is almost useless so I cansel the part and I change the Orion for a Renogy DCC1212-20
 
Depending if your alternator is able to deliver it, you might go for the DCC1212-40 (40A version)
It's currently on sale at the German Renogy store for 130 eur

I think the 40A is more suitable for a 280Ah bank. If you ignore any available solar and plan to be able to use it in the wintertime as well, the 20A might be too slow. If you use 60Ah / day it requires 3 hours of driving to charge with a 20A.

I have gone for the 40A version, and installed a switch on my dash, so I can manually disable it if I want to (for example on a full sunny summer day, the solar will work, so no need to charge it by the alternator in a 2-3 hour drive). The sun is free, so if it takes a whole day to top-up the cells, who cares.
 
Steve,

did you by any chance look into the REC active BMS (4S version)? A bit pricey admittedly, but seems to be well built.

There are a number of satisfied users in the marine world.

MP
I looked at many BMS' when I was shopping them. REC was considered but price point, availability didn't quite meet what I wanted. TinyBMS was high on my list but after buying all the bits it gets pricey. I strongly considered Heltec as well (I started the intro post to them here) but wound up going with Chargery.

Another REALLY GOOD Candidate (minimal mention here) is BesTek which are a more serious board BMS. Check out the HS-15 as a starter.
PCM,BMS,PCB for li-ion,li-polymer,LiFePO4-BesTech Power Co., Ltd

Above being said, the new Chargery BMS*P Series are just about to come out (within a couple of weeks) with Active Balancing RS485/CanBus and more.... BTW: {I am the Chargery user who edited the docs, so.... } ;)
 
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