I have a RAK10721 and I would like to add batteries but I don’t know what type. Can someone please point me to the specs or part numbers for the battery’s for this radio?
Thanks
18650 battery’s ? What’s the line in voltage for solar ? Shouldn’t this thing have a spec sheet somewhere ?
Welcome to RAK forum @johntdyer .
The specs of the battery is here - Solar Battery Lite for Sensor Hub | RAK9154 Backup Power
If you will use your own external power source, we add note on the store description.
OK, but the device itself has four battery spots when you take off the back cover what size batteries are those??
This is a strange one to me as well. Apparently the battery compartment takes LISOC2 ER18505 batteries. But I have been told in another thread that the battery compartment cant be used ? https://forum.rakwireless.com/t/rak-wismesh-repeater-internal-batteries-question/16516
The battery compartments at the back are used for Sensor Hub applications and not on Wismesh Repeater.
Hi. ok so in practical terms does this mean that the components are missing from the PCB to make this work because clearly the spring are still soldered to the PCB. I would very much appreciate if you could clarify this a little more and maybe update your web shop to clearly indicate this.
The reason I am interested is because I would like to use these connections as a way to power the repeater using 3.6V and not 5-12V.
Kind thanks,
Serge
The battery slot at the back are for ER18505. Meshtastic FW of the WisMesh Repeater is customized to work on Solar Battery Lite.
Using ER18505 will not make sense for Meshtastic. For 4000mAh capacity with 10mA consumption, that will be only 400 hours or 16 days (then the battery is empty and cannot be charged).
So why would you put the slots there to support ER18505 batteries if they dont make sense?
Please read attentively on replies @johntdyer as a already answered it. The slots are for SensorHub use case.
SensorHub can have sleep current on uA levels.
uA sleep is NOT possible on Meshtastic. Best case you have is few mA.
Hi,
OK thanks for clarifying this, so if I would like to use the battery contacts to provide a 3.3V regulated supply to the unit can I do it ? According to the following diagram the batteries bypass the buck IC.
Kind thanks,
Serge
Hi @ssozonoff ,
We did not test it for 3.3V. You can use 3.6V supply to battery terminal (same to lithium thionyl chloride types) to power it if you have regulated supply. There is still a regulator between battery terminal and the core/main circuit.
Hi Carl,
Great thanks thats what I was looking for, in that case I assume I can feed it with Lipo’s as well, do you have a reference to the regulator in use ?
Kind Thanks,
Serge
LiPo is 4.2-3.2v range. You need a buck-boost to maintain 3.6v. As for what regulator, there are various options you can find online. I have no particular recommendation. Just make sure that it can deliver enough current when radio send an uplink.
Sorry maybe I mis-understood. You mentioned that “There is still a regulator between battery terminal and the core/main circuit.” Do you have the specifications of this regulator that you mention being between the battery terminal and core/main circuit ?
Thanks,
Serge
We can only guarantee it will work on 3.6v.
Hi.
Please help me out here, I have spent 100’s of dollars on RAK stuff and I am not asking something super complicated. If you can’t tell me the input voltage range of the IC you are using between the battery terminals the main board then give me a reference and I can look it up myself. I dont want a guarantee.
Thanks,
Serge
The Sensorhub has no input range on the battery terminals. It is designed and certified to work/operate on either 3.6V battery slot and the Solar Battery Lite via Weipu outdoor connector.
Which would imply that VDD_NRF is connected directly to the battery terminals and there is no regulator in between as you stated earlier? Maybe I am just being stupid here, I dont know but I have two contradicting pieces of information. One saying I need to supply 3.6V and another saying that there is a regulator between the battery terminals and the main board.
We did not test it for 3.3V. You can use 3.6V supply to battery terminal (same to lithium thionyl chloride types) to power it if you have regulated supply. There is still a regulator between battery terminal and the core/main circuit.
There is a regulator in between and it expects 3.6v input.