Battery & memory capacity

The ReLog has been designed with long term operation in mind. As a result, we have chosen both battery and internal memory to ensure that you can record for as long as you need to without being limited by the specifications. So, as we like to make things simple for our customers, we have put together a few tables below that indicate for how long you can use the three different versions of the ReLog depending on which sample rate that you are using. And for those of you that would like to take a look at the individual specifications for the battery and the internal memory, scroll down to the tables at the bottom of this page. 

ReLog S - Operational capacity

Sample rate (Hz)Runtime in hours
125 Hz260 h
250 Hz236 h
500 Hz216 h
1,000 Hz200 h
2,000 Hz162 h
4,000 Hz144 h
8,000 Hz130 h
16,000 Hz92 h
32,000 Hz46 h

Please note that the numbers above might differ when the ReLog is used outside its normal operating temperature. 

ReLog M - Operational capacity

Sample rate (Hz)Runtime in hoursMax Runtime with
external power source
125 Hz300 h23 000 h
250 Hz272 h11 500 h
500 Hz250 h5 900 h
1,000 Hz230 h2 900 h
2,000 Hz187 h1 400 h
4,000 Hz166 h740 h
8,000 Hz150 h370 h
16,000 Hz142 h185 h
32,000 Hz92 h92 h

Please note that the numbers above might differ when the ReLog is used outside its normal operating temperature. 

What does "external power source" mean?

From some of our customers, we have received inquiries to enable the ReLog to be operational when using an external power source, e.g. a power bank or similar, when the built in Li-Ion battery does provide enough power. So, we have made this option possible on the ReLog M and the ReLog L as these two units are the most commonly used by clients who wish to record for a longer period of time. 

ReLog L - Operational capacity

Sample rate (Hz)Runtime in hoursMax Runtime with
external power source
125 Hz340 h47 000 h
250 Hz309 h23 500 h
500 Hz283 h11 500 h
1,000 Hz261 h5 500 h
2,000 Hz212 h2 600 h
4,000 Hz188 h1 400 h
8,000 Hz170 h720 h
16,000 Hz161 h370 h
32,000 Hz154 h185 h

Please note that the numbers above might differ when the ReLog is used outside its normal operating temperature. 

Battery life

The reason that we provide estimates of battery life is that a Li-ion battery and its performance are affected by several variables at once. The main reasons are that impacts the battery life are:

  • Amount of charge cycles
  • The operating temperature
  • Charging temperature
  • Storage temperature

If you’ve ever lived in, or spent time in, a cold country (we’re based in Sweden so talking from experience here…) you know that an electric car never reaches its target kilometer range. We’ve even tried to turn the AC off while driving in – 5 degrees Celcius to make sure we would reach our destination but it didn’t help much. The moral of that short anecdote? If you will be using the ReLog in cold, or very hot temperatures, pleases be aware that battery life could be significantly shortened and calculate your measurement activities accordingly.

Can the battery be replaced?

No, unfortunately not. Our chosen battery has an estimated cycle life of 500 cycles. One cycle is defined as one charge and one discharge. When approaching 500 cycles and when exceeding it, the capacity of the battery will be decreased.

Due to the different variables (temperature, charing, storage, etc) that the battery will be exposed to, the battery life is estimated to 2-3 years.

But, we do offer a service for both battery replacement as well as calibration of the internal accelerometers. And as the calibration should be done roughly every second year we will offer a service where you send your ReLog to us and we send it back with a new battery and calibrated accelerometers, all for a small fee. Reach out to [email protected] for more information. 

 

Battery specifications

Parametervalue
ChemistryRechargable Lithium Ion
Nominal capacity2,600 mAh - 3,400 mAh
Minimum capacity2,500 - 3,300 mAh
Operating temperature-20°C – 60°C (-4°F to 140°F)
Storage temperature1 month : -20°C – 60°C (-4°F to 140°F)
3 months: -20°C – 45°C (-4°F to 49°F)
1 year: -20°C – 20°C (-4°F to 4°F)
Battery time at full sampling rateReLog S: 80 h
ReLog M: 95 h
ReLog L: 110 h