Finally found a LiFePO4 BMS with Low-temp Charging Protection

[chevymike]

Just wanted to give an update on the battery I put together using this BMS (thread here, https://diysolarforum.com/threads/my-new-diy-100ah-12v-pack-build.8288/ ) So it has been together for almost 2 months now but has not been used. I have not gotten my camper build to the point of installing these so it has basically been in "storage" mode for 2 months. I connect the BT maybe 1-2 times per month to check status of the cells. Here is how much it has drained in the almost two months of sitting.

From first day hooked up (cells at level I got them at, I don't have any charging source for them yet).



Almost two month later, not much of a loss



That might give some people an idea of the drain if sitting unconnected for a given time. The BMS not connected to the BT has very little draw and could easily sit for a year or more without issue. No idea if you have the BT connected full time.

Hope this is helpful.

 

[Kennedyma]

I’ve seen a few people ask about How to cleanly mount three wires on the BMS. I found a Blue Sea 4 terminal bus bar that works great. Here are a few pics of my setup. The bus bar is hot glued to the battery cell.
Edit: Yes I’ve got smaller gauge wire on the connector. I only ever plan on pulling 20 amps from this thing. I also have a 30amp fuse right after the connector in my setup, plus I used the current function in the BMS to limit it to 35 Amps Max.

 

[Sgt Raven]

Just wanted to give an update on the battery I put together using this BMS (thread here, https://diysolarforum.com/threads/my-new-diy-100ah-12v-pack-build.8288/ ) So it has been together for almost 2 months now but has not been used. I have not gotten my camper build to the point of installing these so it has basically been in "storage" mode for 2 months. I connect the BT maybe 1-2 times per month to check status of the cells. Here is how much it has drained in the almost two months of sitting.

From first day hooked up (cells at level I got them at, I don't have any charging source for them yet).

Almost two month later, not much of a loss

That might give some people an idea of the drain if sitting unconnected for a given time. The BMS not connected to the BT has very little draw and could easily sit for a year or more without issue. No idea if you have the BT connected full time.

Hope this is helpful.

13.4V/13.3V is right in the heart of the flat curve of LFP batteries. So it isn't surprising at all.
Charge it up to 13.9V and let it sit. It will slowly drop to 13.4V, then will hold that for a long time....

 

[chevymike]

13.4V/13.3V is right in the heart of the flat curve of LFP batteries. So it isn't surprising at all.
Charge it up to 13.9V and let it sit. It will slowly drop to 13.4V, then will hold that for a long time....

I actually don't have any way of charging them unless I use a standard battery charger. I figured since I knew I would be storing them for a while, this is a good voltage to have them at and was curious if they would discharge at a rate which was faster than I will be getting them installed/charged.

 

[Sgt Raven]

I actually don't have any way of charging them unless I use a standard battery charger. I figured since I knew I would be storing them for a while, this is a good voltage to have them at and was curious if they would discharge at a rate which was faster than I will be getting them installed/charged.

That's a good voltage to store them at. As for a charger, I have used an old Diehard regular 40A car battery charger, to charge my pack. I just set the BMS to cut the charge off, at either a max cell or whole battery voltage. Which ever one tops out first.

 

[berksrunner]

Noooooo check OverkillSolar.com

The center wire does have copper around it. The 120a 3-wire version is a kind of afterthought to the original design.

I am trying to have them tweak the design to better suit our needs. Better connections, more wire size options, more FETs. Im going to have to pay out of pocket for the engineering. Might just redisign the whole thing from scratch in america. But who will manufacture it

Is there a "will prowse" discount code for the Overkill BMS? I'm getting ready to order 3 of 8S version.

Also, do they truly work with Apple iOS??

 

[vtx1029]

Is there a "will prowse" discount code for the Overkill BMS? I'm getting ready to order 3 of 8S version.

Also, do they truly work with Apple iOS??

Yes they work well with IOS search XiaoxiangBMS. you can run the app in demo mode. FYI you will have to pay $5 for the pro version that will let you configure the BMS

 

[MrNatural22]

Is there a "will prowse" discount code for the Overkill BMS? I'm getting ready to order 3 of 8S version.

Also, do they truly work with Apple iOS??

No discount currently. And yes it works well with my iOS. There is a paid version for around $5 I really like it. It also lists all the separate BT BMSs you have.
Can’t seem to get the Android version To work correctly on a spare android phone I have. It only shows first screen and can’t access the parameter screens. ?

 

[teubner]

I set up two of the BMS with 4S 200Ah CALB cells, but can't seem to get the xiaoxiang BMS to work with Android 10.
According to this site, there is no support for Android 10. JBD / Xiaoxiang Smart Bluetooth BMS - wnsnty.xyz
Is there an app that will work with that Bluetooth module and Android 10?

 

[Sgt Raven]

No discount currently. And yes it works well with my iOS. There is a paid version for around $5 I really like it. It also lists all the separate BT BMSs you have.
Can’t seem to get the Android version To work correctly on a spare android phone I have. It only shows first screen and can’t access the parameter screens. ?

Which version of the App? Where did you get that version.

 

[Sgt Raven]

I set up two of the BMS with 4S 200Ah CALB cells, but can't seem to get the xiaoxiang BMS to work with Android 10.
According to this site, there is no support for Android 10. JBD / Xiaoxiang Smart Bluetooth BMS - wnsnty.xyz
Is there an app that will work with that Bluetooth module and Android 10?

Did you try the earlier version? This is the first time I've read about a problem with Android 10 and the App. I would think someone before you would have been running it and posted about it here. Is it something in a new update to A-10?

 

[teubner]

Ignorance on my part.
I had installed android_app_xiaoxiangbms_3.1.1015.apk
I had earlier tried version 2.0.1006.
and I thought that 3.1.1015 installed over top. Instead it created a new icon that I didn't see. 3.1.1015 seems to be working. Thank you.

 

[Sgt Raven]

Ignorance on my part.
I had installed android_app_xiaoxiangbms_3.1.1015.apk
I had earlier tried version 2.0.1006.
and I thought that 3.1.1015 installed over top. Instead it created a new icon that I didn't see. 3.1.1015 seems to be working. Thank you.

The one from the play store was horrible. I got V3.1.1001 from OverKillSolar's github. I haven't updated, because I don't want to lose the statistics it has stored. I'm glad it doesn't have a problem with Android 7, like lots of Apps do. My older Asus 3S-10 tablet still has pretty good specs but they haven't updated the OS. By it's specs, it should be able to run 9 or 10. It's all a racket to make you buy a newer phone/tablet.

 

[MrNatural22]

Which version of the App? Where did you get that version.

This is the version I have currently for iOS

 

[MrNatural22]

It is the android app that isn’t working for me. Only get the first page no other menus.

 

[Sgt Raven]

It is the android app that isn’t working for me. Only get the first page no other menus.

What version of the App do you have, is it the one on the Play Store? The Play Store App is a real old version of the app.
Can you get to the "about this app" page?
Also, which version of Android OS are you running? What make/model Android Phone?

 

[MrNatural22]

The android App Store says its version 3.1.1014 It has a blue icon now it used to have a green one before.
The spare android I’m using for this app is a galaxy sky J7.
Where would I find the new version?

 

[Sgt Raven]

The android App Store says its version 3.1.1014 It has a blue icon now it used to have a green one before.
The spare android I’m using for this app is a galaxy sky J7.
Where would I find the new version?

Probably under "Settings" The Gear Wheel looking icon. Scroll to the bottom under about this phone or software update.
It should say Android xx on there.
I didn't know the Play Store had the newer version. 4 months ago, they were way behind on which version there.
I need to go look now.

 

[MrNatural22]

Phone says android version 6.0.1 what’s with the different colored elephant icons? One blue one green one yellow? Different versions?
The play store only offers the blue.

 

[Sgt Raven]

Phone says android version 6.0.1 what’s with the different colored elephant icons? One blue one green one yellow? Different versions?
The play store only offers the blue.

I know the yellow one showed half the stuff in Chinese and had some big bugs. V3.1.xxxxx is blue. Not sure about the green one.
OK, I'm running V3.1.1001 and Android 7 on my tablet. So it might not be supported in Android 6. A slightly earlier version might work.
Does the Play Store give you a warning about not all things working with your version of Android?
I know I've seen that with some apps and my older tablet. One of my older phones, would not update some apps because of the version of Android on it. The older version of the app still worked but had problems. I saw this with the Gas Buddy App. I got a newer old phone and things updated. My Bank App on my tablet wouldn't update and stopped working, because Android 7 is too old.

ETA: V3.1.1014 has a Play Store warning that it is not optimized for my tablet running Android 7.