HELP...BMS selection should be simple, its not.

[Mark H.]

My problem is simple: Overkill is backordered, Daly gets bad reviews...all I need OR want is a plug and play BMS with low temp cutoff. I don't want to program it, attach relays etc. I am making two batteries, each with 200ah, 12v. 4S. The two batts will be paralleled, each one with a BMS, totaling 400ah

I wanted to go with SOC but they are out of stock till July. I looked at Heltec but am confused as low temp cutoff.

Anyway, everything I've looked at seems to either lack the low temp cutoff OR is a hassle to setup.

Anything out there like the Overkill?

 

[MrM1]

It seems like anything that is not in stock or old stock is back ordered right now. I hope you do find something, but you may just have to wait until Overkill gets more in. That BMS seemed to be unique in its function as you described. (I have been looking for an affordable BMS solution for the past 3 years ~ Overkill seems to fit the bill for me)

 

[ATXist]

I'm new to this stuff as well and in the same boat! I'm about to purchase a Daly 200A, mostly due to lack of alternatives. One point of clarification though, you've given your battery capacity, but what size BMS are you looking for? I think the Overkill ones are either 100A or 120A. If that's enough for your need, there are a few more options out there than if you're looking for larger sizes.

My understanding is Overkill's BMS' are made by JBD, which you can order from AliExpress. Overkill is apparently just imports them, and adds a layer of quality control and warranty protection - both nice things to have! You may want to look into that if you can't find what you're looking for. Good luck!

 

[Mark H.]

I don't mind a larger size, but I was basically trying to emulate the SOC...a 120ah discharge is fine for a 200ah battery as long as connecting 2 batteries will double the max discharge (and charge) rates. But I don't want to wait if I can help it...so I don't care if the BMS is larger than that.

 

[Diysolar123]

well, you really do want a "smart" BMS. I purchased several black box daly units and have zero insight into what is going on; turned out to be a problem.

it seems like jdb on aliexpress has some in stock, well, it will still take the usual few weeks to arrive.

If you want a bms "now", yea, thats an issue. I suppose you could order one of the really cheap 100amp bms units from amazon for now while you wait for the "real deal" to arrive hehe
I mean its $12 with a 2v low cell voltage disconnect , not good, but better than nothing!

 

[Mark H.]

well, you really do want a "smart" BMS. I purchased several black box daly units and have zero insight into what is going on; turned out to be a problem.

it seems like jdb on aliexpress has some in stock, well, it will still take the usual few weeks to arrive.

If you want a bms "now", yea, thats an issue. I suppose you could order one of the really cheap 100amp bms units from amazon for now while you wait for the "real deal" to arrive hehe
I mean its $12 with a 2v low cell voltage disconnect , not good, but better than nothing!

Well... I guess that would make do till Overkill is restocked.

 

[Just John]

My problem is simple: Overkill is backordered, Daly gets bad reviews...all I need OR want is a plug and play BMS with low temp cutoff. I don't want to program it, attach relays etc. I am making two batteries, each with 200ah, 12v. 4S. The two batts will be paralleled, each one with a BMS, totaling 400ah

I wanted to go with SOC but they are out of stock till July. I looked at Heltec but am confused as low temp cutoff.

Anyway, everything I've looked at seems to either lack the low temp cutoff OR is a hassle to setup.

Anything out there like the Overkill?

All I can say is that all of my Daly BMS work fine as a BMS, and have low temperature disconnect. The state of charge doesn't work, the amps in and out is always off by about 2 amps. Everything else works well. I have the 250 amp smart BMS model without a fan in both 24v and 12v.

Obviously it could be better, but the BMS works well.

 

[ATXist]

All I can say is that all of my Daly BMS work fine as a BMS, and have low temperature disconnect. The state of charge doesn't work, the amps in and out is always off by about 2 amps. Everything else works well. I have the 250 amp smart BMS model without a fan in both 24v and 12v.

Obviously it could be better, but the BMS works well.

Apologies if this is a stupid question, but if the BMS doesn't accurately tell you the state of charge, how do you monitor the battery level? Is there another piece of equipment in your standard setup that reports this figure (inverter, charge controller), or do you have to buy a separate battery monitor?

 

[Just John]

Apologies if this is a stupid question, but if the BMS doesn't accurately tell you the state of charge, how do you monitor the battery level? Is there another piece of equipment in your standard setup that reports this figure (inverter, charge controller), or do you have to buy a separate battery monitor?

I use this:

https://smile.amazon.com/gp/product/B07FGFFHC6/

In the near future, I will switch to this:

Amazon.com: Victron Energy SmartShunt 500 amp Battery Monitor (Bluetooth): Automotive

Buy Victron Energy SmartShunt 500 amp Battery Monitor (Bluetooth): Battery Testers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

smile.amazon.com

 

[PaulAtreides]

If the Dalys didn't have such a long lead time I'd sell you my Overkill 4S. I've got a 12V 280Ah battery and I'm thinking about adding an inverter. 120A is pretty much worthless if you're going the inverter route unless you only plan on using a 1kW inverter or less. I need a 1.5kW or preferably 2kW. So that means Daly.....or? Chargery is cool, but no bluetooth. Should I have gone 24V? Probably, but I don't have the space for 8S. So, Daly it is...

 

[Just John]

If the Dalys didn't have such a long lead time I'd sell you my Overkill 4S. I've got a 12V 280Ah battery and I'm thinking about adding an inverter. 120A is pretty much worthless if you're going the inverter route unless you only plan on using a 1kW inverter or less. I need a 1.5kW or preferably 2kW. So that means Daly.....or? Chargery is cool, but no bluetooth. Should I have gone 24V? Probably, but I don't have the space for 8S. So, Daly it is...

I can't speak about currently, but in November of last year it was about 10 days from order to receipt. Daly shipped it via DHL.

 

[A.Justice]

I've used these guys 3 times before, shipping was quick (less than 30 days, from China), and they seem to have a lot of the JBD BMS's in stock.

Home Page - LLT POWER ELECTRONIC

 

[Denis]

I've used the supplier or should say the manufacturer, with fast shipping

On AliExpress and alibaba.

To view 【JiaBaida0168 Store】 on AliExpress with code #_ms5HjXF#, copy the whole sentence and open the app.

Dongguan Jiabaida Electronic Technology Co., Ltd.
https://dgjbd.m.en.alibaba.com/index.html?wx_navbar_transparent=true&tracelog=sns_minisite

 

[LR~Eagle]

I order from Overkill Solar on the April 9th and it was delivered on the April 23rd.
We got a 24v and 48v BMS.

 

[Mark H.]

Apologies if this is a stupid question, but if the BMS doesn't accurately tell you the state of charge, how do you monitor the battery level? Is there another piece of equipment in your standard setup that reports this figure (inverter, charge controller), or do you have to buy a separate battery monitor?

I know you didn't address this to me, BUT...

I'm not concerned with getting the state of charge as I have two separate monitors, the solar controller AND a Bogart monitor for the entire system (including the energy from the RV converter-charger). As they are (or will be) lithium compatible my main concern is just getting a BMS that works without me having to futz with settings and readings...and that provides low temp cutoff. And I'd rather not replace by Renology Solar Control with a Victron (which can provide low temp cutoff).

So it looks like I'll have to go with Daly for now...at least until Overkill is resupplied.

 

[Just John]

And I'd rather not replace by Renology Solar Control with a Victron (which can provide low temp cutoff).

I thought Renogy offered a temperature probe as an add on? I don't have one, but I thought they did. Maybe it's just for lead acid and not low temperature cut off?