Power supplies

Battery

Libelium offers 2 types of battery for the Waspmote OEM line:

  • a 6600 mA·h, rechargeable lithium-ion battery (Li-Ion), with 3.7 V nominal voltage
  • a 52000 mA·h, non-rechargeable battery, with 3.4 V nominal voltage

Waspmote has a control and safety circuit which makes sure the battery charge current is always adequate.

Figure: Battery connector

Battery connection

The figure below shows the connector in which the battery is to be connected. The position of the battery connector is unique, therefore it will always be connected correctly (unless the connector is forced).

Figure: Battery connection

Battery discharging

Figure: Typical discharging curve for battery

Characteristics of the equipment used to generate charging curves:

  • Battery used: 3.7 V - 6600 mA·h battery

As seen above, the rechargeable battery shows a nice slope on its output voltage as its level goes down. Waspmote monitors this voltage in order to calculate the current battery level. However, a rechargeable battery has a very plain discharge graph, so it is not possible to know the remaining energy inside it.

{warning.fa-dot} Notes about the rechargeable battery:

  • When recharging, if the battery is near 0%, it will take some time before the battery level increases.
  • It is normal to see some battery level variations during the charging periods due to the Waspmote charging circuitry. To know the real battery level of the node, it is recommended to measure it when the node is not being recharged and also with sensors and radio modules switched off.

{warning.fa-dot} Warning:
__Batteries with voltage over 3.7 V could irreparably damage Waspmote.
Incorrect battery connection could irreparably damage Waspmote.

{warning.fa-dot} DO NOT TRY TO RECHARGE THE NON-RECHARGEABLE BATTERY, IT MAY EXPLODE AND CAUSE INJURIES AND DESTROY THE EQUIPMENT. USE NON-RECHARGEABLE BATTERIES ONLY WITH DEVICES PROPERLY PREPARED. PLEASE DOUBLE CHECK THIS CONDITION BEFORE CONNECTING THE USB OR THE SOLAR PANEL.

Solar panel

The solar panel must be connected using the cable supplied.

Both the mini USB connector and the solar panel connector allow only one connection position which must be respected ****without being forced into the incorrect position. In this way connection polarity is respected.

Solar panels up to 12 V are allowed. The maximum charging current through the solar panel is 300 mA.

Figure: Solar panel connector

Figure: Solar panel connection

The models supplied by Libelium are shown below:

  • Rigid solar panel
    • 7 V - 500 mA
    • Dimensions: 234 x 160 x 17 mm

Figure: Rigid solar panel

  • Flexible solar panel
    • 7.2 V - 100 mA
    • Dimensions: 284 x 97 x 2 mm

Figure: Flexible solar panel

USB

Figure: Mini-USB connector

Waspmote's USB power sources are:

  • USB to PC connection
  • USB to 220 V connection
  • USB to vehicle connector connection

The charging voltage through the USB has to be 5 V.

The maximum charging current through the USB is 480 mA (100 mA in batches since summer 2018).

The mini USB connector must be standard mini USB model B.

Figure: Possible connections for the USB

The models supplied by Libelium are shown below:

Figure: 220 V AC – USB adapter

Figure: 12 V DC – USB car lighter adapter