Blue Tooth Battery Fun

[Rbertalotto]

Blue Tooth fun.....I have two, Blue Tooth capable, 12v, 100aH, Lithium batteries in parallel in my travel trailer. One stopped connecting to Blue Tooth on my phone and tablet. I called the manufacturer and they wanted me to send the battery back soi they could decide if it needed to be replaced. I took the batteries out of the camper and brought them into the garage. The battery that wasn't responding showed 10.3v......I hooked it up to a Victron Smart 30a charger and immediately the BT worked and it showed 13.6v and 100% charge!.......I left both batteries in the garage overnight without anything connected to them. No charger. Today, both batteries would not connect to BT. So I simply touched the charger leads to the terminals and BOOM....both immediately responded to BT.....So, my question, if the batteries are not under a load or being charged, do they "go to sleep" and need to be woken up with a jolt of electricity......Is this normal or unique to these batteries?

 

[justinm001]

What model battery? That would make sense as I don't think you'd want your batteries to die because the BT module is slowly draining them when not in use.

 

[Rbertalotto]

Thanks! I'd rather not disclose the battery make as the "Cheerio Pissers" will go crazy as to why I shouldn't buy this brand.....

 

[Bob B]

This behavior is not typical of any Bluetooth BMS I have used .... Without some specific info about the battery or BMS it's going to be difficult for good info.

If the batteries were in parallel, they should have been at approximately the same charge level .... Not a good idea to let them get that low. It's entirely possible the odd behavior is because of the low SOC.

It is obvious that a battery at 10.3V didn't instantaneously go from there to fully charged when connecting a charger ..... Seems like the BMS is determining SOC from a voltage reading of the pack.

 

[Nobodybusiness]

Cheerio Pissers

Is that a Group of Drunk Englishman saying Hello??

 

[RCinFLA]

It may not be the BT module going to sleep but the microcontroller in the BMS that creates the BT data communication that is shutting down to prevent further discharging of battery. Once you charge battery it will likely be okay.

 

[Rbertalotto]

It may not be the BT module going to sleep but the microcontroller in the BMS that creates the BT data communication that is shutting down to prevent further discharging of battery. Once you charge battery it will likely be okay.

Once I simply touched thr charger to the battery terminals the BT turned on and showed 13.6v and 100% SOC

 

[mikefitz]

simply touched thr charger to the battery terminals the BT turned on and showed 13.6v and 100% SOC

Some manufactures have this built into the BMS. If no power in/ out the battery for a time, it shuts down. Renogy brand batteries, for example, have this feature.