48V 50Ah Stackable Battery VS 48V 50Ah Server Rack Battery

[cs1234]

I like both of you but that answer also misses the mark . Usually with bluetooth, you pair the device (battery in this case) with the phone that you are going to control it with. That sets up a shared cryptographic key between the battery and the phone, which in principle is much more secure than a password. So a password wouldn't help that much.

The bluetooth batteries I've seen so far don't even ask you for a bluetooth pairing password. You just select the battery from a list of detected batteries (bluetooth devices) in the area, and it automatically connects and lets you play around with them. Anybody with the app (which is freely available) can access/modify any settings the battery allows via bluetooth. It's not as though the battery only allows one paired device, and then blocks all further pairing attempts.

Contrast this with a Victron bluetooth device which has a default pairing password, but you can change it once you connect to it so no other devices can pair with it without that new pairing password. You can also flat out disable bluetooth on the Victron devices I've used so far.. reenabling it again if necessary using an alternate non bluetooth means.

 

[werepuppy]

Pairing passwords aren't used that often, but you usually pair by pressing a "pairing" button on the device. So you need physical access to the device in order to press the button. Bluetooth headsets and speakers that I've seen work that way. Do your batteries not have that?

 

[cs1234]

Pairing passwords aren't used that often, but you usually pair by pressing a "pairing" button on the device. So you need physical access to the device in order to press the button. Bluetooth headsets and speakers that I've seen work that way. Do your batteries not have that?

They sure don't. They are always just broadcasting pairing available I guess. Hence the request for a customizable pairing password, physical bluetooth cutoff, or a physical pairing button. Whatever one of those methods they want, anything would be better than what they do now.

 

[werepuppy]

That's pretty interesting. Can you test it? Pair your battery with your normal phone, and then see if you can pair a second phone without physical access? That's pretty terrible if you can. Even my 5 dollar bluetooth speaker has a pairing button. Of course I use the analog (wired) input instead of bluetooth anyway, heh.

 

[cs1234]

That's pretty interesting. Can you test it? Pair your battery with your normal phone, and then see if you can pair a second phone without physical access? That's pretty terrible if you can. Even my 5 dollar bluetooth speaker has a pairing button. Of course I use the analog (wired) input instead of bluetooth anyway, heh.

I don't have one of these EW batteries in question to test. I have other brands of bluetooth batteries. They've all used similar bluetooth apps though, and I've connected to them using multiple bluetooth phones without problem.

Watching reviews of these EW batteries and reading EWs response when asked if we can physically cut off bluetooth has led me to believe they function in the exact same way.

I'm sure somebody here will correct me if I'm wrong about not needing a password or pairing button on these EW batteries.

 

[werepuppy]

As another question (I should really check the manual), does the interface for these batteries usually allow reading the battery temperature? Preferably separately for each individual cell, but a single sensor inside the battery case is much better than nothing.

 

[cs1234]

As another question (I should really check the manual), does the interface for these batteries usually allow reading the battery temperature? Preferably separately for each individual cell, but a single sensor inside the battery case is much better than nothing.

I went to go look using my phone, and then realized I care so little about the apps these days that I hadn't reinstalled any of them when I got my latest phone. I don't recall if the apps showed any temperature sensors or not. Some of them might.. maybe somebody else can chime in.

 

[werepuppy]

I looked at the manual for the inverter and it was really good about specifying what was in the comms protocol, so I should check the battery manual too.

Re Bluetooth, I don't want to scare anyone away from the batteries. My phone has Bluetooth and I carry it everywhere without worrying too much. I usually do keep the Bluetooth turned off in the settings menu though. It's just a matter of wanting to avoid unnecessary vulnerability.

Another question: is it ok to mix 50AH and 100AH batteries in a single stack?

 

[ECO-WORTHY Sunny]

I looked at the manual for the inverter and it was really good about specifying what was in the comms protocol, so I should check the battery manual too.

Re Bluetooth, I don't want to scare anyone away from the batteries. My phone has Bluetooth and I carry it everywhere without worrying too much. I usually do keep the Bluetooth turned off in the settings menu though. It's just a matter of wanting to avoid unnecessary vulnerability.

Another question: is it ok to mix 50AH and 100AH batteries in a single stack?

We’re not able to monitor the temperature of each individual cell at the moment. However, our battery is equipped with four temperature sensor probes that are evenly distributed internally, which is more than sufficient for monitoring the battery’s internal temperature. You can connect the battery to your phone via Bluetooth to keep an eye on the temperature, or you can link it to a host computer using the RS485 interface to check the battery’s operating temperature and other information.(check the fig. below)

Regarding your second question, unfortunately, the 50Ah and 100Ah batteries can’t be used together. There are significant differences between individual batteries in a battery pack, which can directly affect the pack’s efficiency, lifespan, and safety. Just a friendly reminder, no matter the brand, when combining batteries into a pack, it’s crucial to ensure consistency in voltage, capacity, and internal resistance, and to set appropriate parameters.

As for the concerns about the Bluetooth function that have been raised earlier, we’re currently working on developing an encryption feature for the Bluetooth. So, stay tuned!

 

[werepuppy]

As for the concerns about the Bluetooth function that have been raised earlier, we’re currently working on developing an encryption feature for the Bluetooth. So, stay tuned!

Be careful with this, it's very easy to make mistakes. I really don't see a reason to develop anything like that yourself. Just use the pairing capability already present in the Bluetooth hardware. Just make it so you can't pair a phone with the battery unless you have physical access to the battery. Like the bluetooth keyboard I sometimes use with my phone has a "connect" button, and you have to press that button in order to pair.

Some fancier devices have a 4 digit display on the device, and the phone app also shows 4 digits, and the user makes sure that the two numbers match before allowing pairing. TBH I haven't seen that in a while, and I guess your battery has no display.

I might try to read up on this later. I looked into it years ago but I don't remember much now. The encryption built into Bluetooth is actually pretty good though.

 

[Wolfpack7483]

I can confirm that the Enerkey 4s does not fit inside the stackable 50ah battery. There is no room inside. I may see if I can remove the "indented handle" on the opposite end from the terminals and cut a pathway for the wiring.

I like the form factor of the stackable for a mobile application, but future purchases for this purpose will either be the DC House version with bluetooth or the server rack version. Does anyone what the BMS model is in the DC House. I may end up swapping out the BMS on the stackable that I have.

 

[wpns]

Just make it so you can't pair a phone with the battery unless you have physical access to the battery.

Indeed. You are going to need a physical (or magnetic reed switch?) reset button for when you've forgotten the password, so might as well just make it a pairing button.

 

[BarracudaBob]

I can confirm that the Enerkey 4s does not fit inside the stackable 50ah battery. There is no room inside. I may see if I can remove the "indented handle" on the opposite end from the terminals and cut a pathway for the wiring.

I like the form factor of the stackable for a mobile application, but future purchases for this purpose will either be the DC House version with bluetooth or the server rack version. Does anyone what the BMS model is in the DC House. I may end up swapping out the BMS on the stackable that I have.

If you cycle it from top down the bottom bounds three times you probably don't need to put it in there permanently.

Just getting it all aligned up together is usually enough.

 

[BarracudaBob]

There was talk about installing an external balance port where you could plug it in the front. This way just plugging in one necessary.

 

[Wolfpack7483]

I bought a stackable for my mobile build, and also have a server rack unit on the way to compare. 1st thing I tried to do with the stackable was the top balance. Learned a valuable lesson, don't believe what you think your eyes tell you - verify everything. I was in a hurry to hook up the Enerkey, before heading out of town for the 4th. Hooked everything up, and "nothing" on the Enerkey.

Finally figured out that the red cable on the stackable was the negative, and the black was positive. None of the balance leads are numbered on this battery. If I'd paid attention, I should have verified before attaching all the leads. I did check the voltages for each cell. They were all just exactly what I expected, just never noticed the little - sign on the Fluke. I plan to pay closer attention in the future. Attached is a picture of the properly wired Enerkey.

 

[42OhmsPA]

Regarding your second question, unfortunately, the 50Ah and 100Ah batteries can’t be used together. There are significant differences between individual batteries in a battery pack, which can directly affect the pack’s efficiency, lifespan, and safety. Just a friendly reminder, no matter the brand, when combining batteries into a pack, it’s crucial to ensure consistency in voltage, capacity, and internal resistance, and to set appropriate parameters.

As long as the cell count is the same, why does the capacity matter?
The lower Ah would drain first and the larger would take over.
As long as C rates aren't to high on any individual packs I don't see any issues.

 

[wpns]

The lower Ah would drain first and the larger would take over

It’s actually better than that, if the wiring is comparable, the larger pack will supply more current in proportion to its capacity, but they will both supply current at all times, and both willstart and end at 100 and 0%.

 

[BarracudaBob]

I bought a stackable for my mobile build, and also have a server rack unit on the way to compare. 1st thing I tried to do with the stackable was the top balance. Learned a valuable lesson, don't believe what you think your eyes tell you - verify everything. I was in a hurry to hook up the Enerkey, before heading out of town for the 4th. Hooked everything up, and "nothing" on the Enerkey.

Finally figured out that the red cable on the stackable was the negative, and the black was positive. None of the balance leads are numbered on this battery. If I'd paid attention, I should have verified before attaching all the leads. I did check the voltages for each cell. They were all just exactly what I expected, just never noticed the little - sign on the Fluke. I plan to pay closer attention in the future. Attached is a picture of the properly wired Enerkey.View attachment 310278

I have been helping others and asked for notes of how to improve the process. One thing that came up was to label every terminal like -1, +1, -2, +2, etc.. with a black marker. I started doing this myself. In the 14.3K 280ah the negative terminal has a red wire so almost did it myself.

I found the balancer is resilient and survived having the wire off a couple of cells.

Another note is that when the battery/cells get on the high end of their charge things change fast. The lighter the voltage the lower the power supply current. It isn't to hard for one cell to jump way up.

On the rack batteries I reprogram the bms to allow 3.650V/Cell and 58.4V/Pac so the BMS is in the way of the power supply. A special balance parameters.. To bad no room inside.

Top Balance, Drain Down, and Top balance will usually do it. The last Beasty 280ah too 3 cycles but doing just fine now.

It would be cool to have a 16 or more connector on the battery for checking and tuneups.

 

[BarracudaBob]

I would curious and just looked for a connector on DiGiKey

Something that @marionw talked about a while back

Receptacle:

SRCN2A25-16S
CONN RCPT FMALE 16P SOLDER CUP

​

 

[wpns]

It would be cool to have a 16 or more connector on the battery for checking and tuneups.

With an appropriate fuse on each and every pin!

 

[BarracudaBob]

With an appropriate fuse on each and every pin!

Pico fuse or NTC resettable devices. I used to use those in some mobile electronics.

 

[Wolfpack7483]

I have been helping others and asked for notes of how to improve the process. One thing that came up was to label every terminal like -1, +1, -2, +2, etc.. with a black marker. I started doing this myself. In the 14.3K 280ah the negative terminal has a red wire so almost did it myself.

I found the balancer is resilient and survived having the wire off a couple of cells.

Another note is that when the battery/cells get on the high end of their charge things change fast. The lighter the voltage the lower the power supply current. It isn't to hard for one cell to jump way up.

On the rack batteries I reprogram the bms to allow 3.650V/Cell and 58.4V/Pac so the BMS is in the way of the power supply. A special balance parameters.. To bad no room inside.

Top Balance, Drain Down, and Top balance will usually do it. The last Beasty 280ah too 3 cycles but doing just fine now.

It would be cool to have a 16 or more connector on the battery for checking and tuneups.

It's hard to see in the picture, but I did # the cells (actually re-numbered) with a black marker. The incorrect #s came off very easily with a little alcohol. Was surprised that the Enerkey wasn't active until after 3.42v. It's on the drain down now with the dehumidifier. At around 600w, it'll be a little over 4 hours.

 

[K7TH]

If you cycle it from top down the bottom bounds three times you probably don't need to put it in there permanently.

Just getting it all aligned up together is usually enough.

I believe its JBD from prior reading or videos on YT.

 

[Wolfpack7483]

I believe its JBD from prior reading or videos on YT.

It's a JBD TP205001-T, from video. Thinking of replacing it with a Bluetooth version from Ali-Express. Similar form factor is around $35. I just need to figure out how to access it. In the YT video I watched, there was an external bolt holding the handle in place. The current version no longer has the bolt, and you need to remove the handle to access the BMS.

 

[wpns]

Pico fuse

AIC 300A, at which point the wire becomes the fuse?

or NTC resettable devices.

I can’t parse the specs, will they take 60V at a few amps?

I used to use those in some mobile electronics.

Both decent ideas, T class fuses would be way overkill.