nPM Fuel Gauge board

Hardware tool to profile batteries to be used for fuel gauge

The nPM Fuel Gauge board (nPM FG) connects to a compatible Nordic Semiconductor evaluation kit. The purpose of the board is to act as a constant current sink device during battery profiling with nPM PowerUP desktop software. The battery model generated in nPM PowerUP can be used for evaluation of fuel gauge in nPM PowerUP and exported as an include file for use in any application using the Nordic Fuel Gauge algorithm.  

To use the nPM Fuel Gauge board you also need a compatible evaluation kit

Currently supported kits: 

Key features

Connector for compatible Nordic evaluation kits

Constant current sink with heat spreader

Used for profiling batteries for Fuel Gauge applications

Status indicator LEDs 

Low power high accuracy fuel gauging

tailored for embedded IoT

Estimating state-of-charge

in lithium batteries is crucial for optimizing performance and ensuring safe operation. There are several methods used to estimate the state-of-charge of single-cell lithium batteries. 

All methods have their benefits and drawbacks, but some benefits are more desired and some drawbacks are less severe than others. For the nPM1300, we decided that algorithm based fuel gauging was the way to go.

 Technology

Nordic Fuel Gauge

Open circuit voltage measuring

Coloumb counting fuel gauge IC 

Pros

 + High accuracy  + No additional energy usage  + Best accuracy 

 + Ultra-low power consumption  + No additional cost added to your bill-of-materials

 + No current draw at system-off    

 + No added cost to your bill-of-materials    
       
 

Cons

 - Needs to be supported by PMIC  - Very low accuracy - Draws current even at system-off to keep coloumb counter running
     - Severly affected by temperature - Expensive, adds components to your bill-of-materials (BoM)

To take advantage of the fuel gauging capabilities of the nPM1300, you can read the application note explaining how to create a virtual model of your battery for use with the fuel gauge sample in the nRF Connect SDK. 

For selected lithium ion polymer batteries from Renata, Nordic is also providing turnkey battery models ready to use. Scroll down to se the list of supported batteries. 

Learn how

Guide to profile your batteries with nPM FG

Low power high accuracy fuel gauging tailored for embedded IoT

To accurately estimate the battery state-of-charge in percent, from 0 to 100 %, the nPM1300's fuel gauge functionality uses a virtual model of your battery along with the battery's temperature, voltage and the current measured by the PMIC. The estimation algorithm can then be run on any Arm Cortex M4 or M33, like those found in the nRF52, nRF53 and nRF91 Series and does not require additional hardware beyond this.  

The battery model is created by doing an analysis of your specific battery, in your own lab, with the help of the nPM1300 Evaluation Kit along with a dedicated nPM Fuel Gauge board. 

Learn how to profile batteries from the comfort of your own lab:  

Fuel Gauging Webinar

nPM PowerUP walktrough Webinar

Download pre-profiled battery models

Selected version
ICP641620PA-01 - 165 mAh Renata

Changelog:

ICP641620PA-01 - 165 mAh Renata

ICP621333PA-01 - 240 mAh Renata

ICP403029PL02 - 325 mAh Renata

ICP582035PR-01 - 340 mAh Renata

ICP582930PR-01 - 450 mAh Renata

ICP632136HPST - 520 mAh Renata

ICP682828HPMT - 560 mAh Renata

ICP622540PMT - 600 mAh Renata