280ah DIY vs 300ah chins

[shawn6596]

I plan to have a 12v bank around 600ah total for my coach. My current setup is 912ah 12v FLA, 2kw inverter, and 2kw of solar on the roof. I am looking at 2 4s 280ah bank with a 120a overkill and heltec active balancer, or 2 300ah drop in chins. the price difference is $800.

The difference in shipping is 2 months minimum for the DIY or a week for the chins. I have time If I order now, we'll be in this location until December.

I travel full time so I would have to invest in a charger for top balancing, but I wondered if having a 5a heltec would eliminate the need to individually balance the cells.

Amazon.com

Please share your perspective on this.


Which way would you go, and why?

 

[HOU_Castle]

Question: Have you ever built LFP batteries (12V)?

 

[shawn6596]

Question: Have you ever built LFP batteries (12V)?

I have not. That being said I have been lightly researching it for over a year, and I am very skilled with my hands. I designed and installed my 2000w solar system with zero experience, and that was easy. It is 2 1000w arrays feeding 200vdc to midnight 250-cp controllers. we have been look at buying a house and getting off the road, but people are out of their minds, so it looks like we are going to winter off grid in vegas again because I have work contacts there. If we stayed in a cg our current bank could be nursed along since the solar keeps it charged, but if we are off grid I don't trust the lead more than overnight. I'm just trying to get my ducks in a row while I have time. the reason I am leaning towards the DIY is because of all the BMS problems I have been reading about the chins. what ever road I take I want safety to be priority for my family. I have seen tons of videos on assembling a DIY bank, it's not that hard. Unless you have something I need to see. I love a good lesson, thats why I am here. There is more experience here than I could hope to learn in a life time.

 

[HOU_Castle]

I have not. That being said I have been lightly researching it for over a year, and I am very skilled with my hands. I designed and installed my 2000w solar system with zero experience, and that was easy. It is 2 1000w arrays feeding 200vdc to midnight 250-cp controllers. we have been look at buying a house and getting off the road, but people are out of their minds, so it looks like we are going to winter off grid in vegas again because I have work contacts there. If we stayed in a cg our current bank could be nursed along since the solar keeps it charged, but if we are off grid I don't trust the lead more than overnight. I'm just trying to get my ducks in a row while I have time. the reason I am leaning towards the DIY is because of all the BMS problems I have been reading about the chins. what ever road I take I want safety to be priority for my family. I have seen tons of videos on assembling a DIY bank, it's not that hard. Unless you have something I need to see. I love a good lesson, thats why I am here. There is more experience here than I could hope to learn in a life time.

Do you know every risk of building LFP battery? required PPE? This is dangerous stuff for newbie. I just need you to weigh in risks vs. $800 saving. Is it worth? Do you know basic electricity knowledge, etc.? If you search "safety" keyword in this forum, you will see how many folks were in near-miss accident, from close call to loosing his home and his loves one.

 

[shawn6596]

Do you know every risk of building LFP battery? required PPE? This is dangerous stuff for newbie. I just need you to weigh in risks vs. $800 saving. Is it worth? Do you know basic electricity knowledge, etc.? If you search "safety" keyword in this forum, you will see how many folks were in near-miss accident, from close call to loosing his home and his loves one.

Having read you safety post I am fully aware of some of the dangers you showed. I appreciate your perspective on liability. I would never play with pouch cells, thats one reason I stayed away from the LG banks on battery hookups. While I am a novice, I'm not that new. the assembly of a basic 12v bank is well with in my abilities. I'm guessing your concerns are stemming from me asking If I can skit top balancing by using an active balancer. I know the proper way is to top balance. I was just spit balling weather it could work or not. I've also wondered if I could use an overkill BMS to trigger a 400a latching relay. In the end I know I would be better off building separate 280ah 4s banks and paralleling them to gain a higher amperage draw. I do appreciate that you are looking out for the safety of others.

 

[Pappion]

I ordered cells thru Amazon. Shipments failed to reach me in time. Shipment to my sons house in Raleigh NC arrived weeks early. If your in an outlying area, very likely UPS will sit on it in a big city whare house until they get a full load of special handling items.