Tag: internal resistance

CITYSAX 160Ah LiFeYPO4 battery discharge and teardown (WHL #51)

Speaking of electric cars: A colleague recently bought a used electric car and (obviously!) contacted me in order to diagnose/troubleshoot it. Sadly he was able to sell it for a profit before we got it fully fixed, so no live data recordings, no power/torque graphs, no nothing to show here. But he left me a dead cell for which he got a replacement from the seller right away, as the traction battery had voltage dips under load that indicated (at least) one damaged cell.

If servicing individual battery cells sounds a bit strange for a modern electric car, that’s because we’re talking about a CITYSAX from a company that is conveniently named the same. […]


16 Bit I2C ADS1115 Module ADC 4 channel with Pro Gain Amplifier RPi (WHL #26)

Meep. We finally have a new product review, after all that editorial, recap and electronic load rubbish ;)

Today’s item in the mail is an I²C ADC on a small PCB, running four channels (or two differential ones) with 16 bit precision. Sounds nice? Well, if it holds the claimed specs, it IS a nice product! I bought it in mid-June on AliExpress for 2.06 USD. Adafruit, by the way, charges 15 bucks for the exact same thing. Do I smell profit margin?

Here’s how it looks straight out of the ESD bag:

Backside is a tad boring (keep the VDD in mind):

(there’s a floating island on the GND plane, boo!)

So, what does the friendly Asian seller claim? […]