Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Bms for 16s
#1
Hi

New here and pretty new to the subject too so by all means treat me as an idiot ?

I have 5 bmw i8 packs . Each pack is 16s . I have tested them and each cell in the pack is at 4v so each pack is 64v

I’m planning on joining them in parallel for 16s5p

I was willing to buy a batrium but they have said watchmon 4 isn’t suitable and their other option only goes to 15s

I’m planning to use this for solar storage to charge my electric car in an effort to be 100% environmental in my driving.

I’ve spent the last week looking at various bms , cheap ones , expensive ones etc and I’m totally lost.

I’m assuming the cheapest would be to have Daly or something like that for each pack ?

I’m struggling to make a choice as my knowledge is probably not good enough yet. What size bms ? 100a 150a . I’m assuming I want a bms where I can choose the minimum cell voltage and maximum?

Am i on the right track or completely out ?

Which Daly might work for this ?
I have also come across Chargery BMS16T

Would that work for me ?
Reply
#2
https://www.orionbms.com/
http://www.rec-bms.com/
https://emusbms.com/products-catalogue

https://www.energusps.com/shop/product/t...0a-750a-36 not really in the same class as the above bms's
I would go with something besides a cheap bms spend money to protect your batteries.
DC to DC charging? AC charging of ev?
most cheap bms's are overated in power handling.
Later floyd
Patalhetas likes this post
Reply
#3
>I was willing to buy a batrium but they have said watchmon 4 isn’t suitable and their other option only goes to 15s
Not sure who 'they said' is - but Batrium will work very well.  I use Batrium and I use Watchmon 4 with 84 packs (84 longmons).   Batrium wise you could do....
- Watchmon 4 + 16 longmons - note that the longmons don't have to be on the battery itself, you just have to connect + / - from each longmon to each cell.  One reason they are 'typically' place physically near the cells is that they have temp sensors - so can monitor the temp of each cell and for convienence ...  but its not functionally necessary.
- Watchmon 5 - this has 16 'longmons' built in - so you just run wires to the cells from the central unit.   This is a little cheaper and is less balance power - but it will definately work for your application.

VERY CHEAP SIDE - you could consider something like this - https://www.ebay.com/itm/Ant-BMS-7S-to-1...SwMste~JzP   -  but I've had mixed results.  For example, I made a simple mistake and blew one up.  Another burned up an internal resistor for some reason - and the others worked.    But they are cheap compared to Batrium and others Smile

>What size bms ? 100a 150a . I’m assuming I want a bms where I can choose the minimum cell voltage and maximum?
In Batrium you can.      Amps - Batrium itself doesn't care about this but till will trigger (on events you chose) to send a current to an external shunt-trip - which you need to buy.   In many our or cases - we use used ABB SACE for higher amps.     In my case, I needed 400amp.    The amps are whatever you plan to draw from the battery bank...  you only need a shunt-trip to handle your largest load.   Here's an example of a used ABB SACE - https://www.ebay.com/itm/ABB-SACE-S5-400...Swq7ldcpoh - but you need to pay attention the 'trip voltage' - a lot of use 24vdc models.
Reply
#4
I use chargery 16s for my 16s Chevy volt packs. It’s working well.
Reply
#5
(10-23-2020, 12:48 AM)Cheap 4-life Wrote: I use chargery 16s for my 16s Chevy volt packs.  It’s working well.
On the affordable side - I have one operating as well - but another burnt up and a 3rd blew up when I somehow touched the temp sensor to a cell in the pack.   So I've had mixed results; however, I don't see any for sale right now so I didn't mention it above.   I agree it's an alternative and I like them - but they can be finicky.
Reply
#6
Thanks everyone. I’m blown away by the response.

Floydr a couple there I haven’t looked at so will study them.

Offgridinthecity: I contacted batrium by email and they weren’t overly helpful. It was actually them that sent me here for advice.

Watchmon 5 Only seems to go to a maximum of 15s which is why they said that wouldn’t work but they didn’t elaborate on why watchmon 4 wasn’t suitable so it is probably because I can’t attach them to the cells as you explained. I must admit it was my first choice as once I have done my learning on these batteries I’ll probably go on to more expensive ones. For the moment while learning I just want to power my charging of the car but eventually I’d love to do the whole house.
You mentioned 16 longmons , I have 5 packs of 16s so would I just buy 80 longmons to monitor the 16 cells in each pack ?

Cheapforlife: that’s good to know , I have one in my AliExpress basket as a possibility. Do you have one for each pack ?

Again thanks for all the help. I appreciate helping newbies can be a thankless task sometimes!!

Picture of 1 of 5 batteries
Reply
#7
The reason they state longmons isnt the best choice is since you have a shared loom. If you can put wires to each battery without sharing the wiring with each longmon you can still use them and yes unless you plan on hooking each of them up together you need 80 longmons. So you basically have to scrap current wiring and put out 2 wires for each longmon instead of what you have today with 1 wire for each cell. You need 2 since each longmon connect there.
they should also sit fairly close to the cell so you should not extend the wiring 1 meter and such. Thats why they arent the best option.

Beware that you also need inverter/charger that can tolerate that voltage. 16s Liion is the high range and not all cheap systems like it.

Btw DIY BMS also have somewhat the option like Batrium have if the cost of going 80 mons is an issue.

I use Batrium btw but have tested many others. Currently im working with a new system with DIY Bms.
NOTE! My links supplied in this message may be affiliated with Ebay and by clicking on them you agree on the terms.
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Reply
#8
If you join the cells in parallel    "I’m planning on joining them in parallel for 16s5p..."     then you only need 16 longmons (for Batrium).    As @Daromer pointed out - you do have to have a + and - for each longmon to each set of parallel group of cells...  but if you're going to parallel the cells then  take this into account and wire it so you have tap wires coming off for longmon use.       And will have to be watchmon 4.      

I didn't realize WM5 is only 15 cells in series - weird as I saw it was more than 14 (in youtubes) and just assumed it would do 16 for LifePO4.    But yep, its only 10-15 cells per description here - https://www.batrium.com/collections/cent...chmon5-exp   (My bad for referencing for 16s).    I wonder why they limited it to 15...  and not 16 so LifePO4 (48v nominal) could be an alternative use?

TMI... Smile    Another thing to consider in relation to BMS is how you like to monitor things.   It ranges from Android apps to internet/PCs to custom code.    For me, I like to see stats/details of what's happening without custom code.   But others just want it to work quietly and not bother them.    I choose Batrium exactly because its internet (wifi) and PC (windows) and has excess detail on all aspect.     Don't mean to push Batrium...   you may be the 'don't bother me type' and in that case something that 'just does the job' may be all you need.
Reply
#9
They didnt limit it. The Common size is 14 and they use built in chip that is 10-15. Thats the Common size chip you find for balancing Wink just look at Texas. Next step is alot higher
NOTE! My links supplied in this message may be affiliated with Ebay and by clicking on them you agree on the terms.
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Reply
#10
(10-23-2020, 03:44 PM)OffGridInTheCity Wrote: If you join the cells in parallel    "I’m planning on joining them in parallel for 16s5p..."     then you only need 16 longmons (for Batrium).    As @Daromer pointed out - you do have to have a + and - for each longmon to each set of parallel group of cells...  but if you're going to parallel the cells then  take this into account and wire it so you have tap wires coming off for longmon use.       And will have to be watchmon 4.      

I didn't realize WM5 is only 15 cells in series - weird as I saw it was more than 14 (in youtubes) and just assumed it would do 16 for LifePO4.    But yep, its only 10-15 cells per description here - https://www.batrium.com/collections/cent...chmon5-exp   (My bad for referencing for 16s).    I wonder why they limited it to 15...  and not 16 so LifePO4 (48v nominal) could be an alternative use?

TMI... Smile    Another thing to consider in relation to BMS is how you like to monitor things.   It ranges from Android apps to internet/PCs to custom code.    For me, I like to see stats/details of what's happening without custom code.   But others just want it to work quietly and not bother them.    I choose Batrium exactly because its internet (wifi) and PC (windows) and has excess detail on all aspect.     Don't mean to push Batrium...   you may be the 'don't bother me type' and in that case something that 'just does the job' may be all you need.


Ok so now I’m a little confused. Each pack has 16 cells making up 64v I was planning on paralleling the whole pack let’s say For simplicity 64v 20ah with the other 4 packs so it would be - 64v 100ah battery. I’m not changing any wiring in each pack. I had assumed I would just parallel one pack to the next and the next and I would need to monitor each cell so 16 cells x 5 = 80 longmons . Maybe (very possibly) I’m misunderstanding something as I saw someone else say 16 but I don’t see how if you group cells together in parallel and monitor them with 1 longmon how would you guarantee that all the cells stayed at exactly the same voltage ?

(10-23-2020, 11:40 AM)daromer Wrote: The reason they state longmons isnt the best choice is since you have a shared loom. If you can put wires to each battery without sharing the wiring with each longmon you can still use them and yes unless you plan on hooking each of them up together you need 80 longmons. So you basically have to scrap current wiring and put out 2 wires for each longmon instead of what you have today with 1 wire for each cell. You need 2 since each longmon connect there.
they should also sit fairly close to the cell so you should not extend the wiring 1 meter and such. Thats why they arent the best option.

Beware that you also need inverter/charger that can tolerate that voltage. 16s Liion is the high range and not all cheap systems like it.

Btw DIY BMS also have somewhat the option like Batrium have if the cost of going 80 mons is an issue.

I use Batrium btw but have tested many others. Currently im working with a new system with DIY Bms.

Thanks for the reply daromer.

I was planning on using Victron which I think will work.
I had a quick look at diybms bit my head started to hurt Smile I’ll take another look tonight but I can afford the batrium if need be. 80 longmons or 16 ? Smile
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)