Post-Failure Autopsy And Analysis Of An LFP Battery

April 2, 2026 by Maya Posch 8 Comments

Recently [Kerry Wong] had one of his Cyclenbatt LiFePO₄ batteries die after only a few dozen cycles, with a normal voltage still present on the terminals. One of the symptoms was that as soon as you try to charge it, the voltage goes up very rapidly to above 14 V due to what appears to be high internal resistance, and vice versa for discharging. In addition, the Bluetooth feature of the BMS appeared to have died as well, making non-invasive diagnostics somewhat tricky.

Close-up of the BMS. (Credit: Kerry Wong, YouTube)

After gently cutting open the plastic case, [Kerry] was greeted by the happily blinking blue LED of the Bluetooth module and deepening the mystery. Overall the build quality looks to be pretty good, with no loose cables as seen with certain other LFP batteries.

Cell voltages measured normal, with no significant imbalance. Next was measuring the internal resistance, which showed a clear issue. One of the cells was reading over 3 Ohms, whereas the others were in the milli-Ohm range. This would definitely explain the issues with charging and discharging, with a single bad cell causing most of the issues.

Of course, why the Bluetooth feature failed remains a mystery, and there’s still a lingering question on whether the BMS practiced proper balancing between the cells, as this can also cause issues over time.

Continue reading “Post-Failure Autopsy And Analysis Of An LFP Battery” →

Soviet CDs And CD Players Existed, And They Were Strange

March 29, 2026 by Maya Posch 11 Comments

Until the fall of the Soviet Union around 1990 you’d be forgiven as a proud Soviet citizen for thinking that the USSR’s technology was on par with the decadent West. After the Iron Curtain lifted it became however quite clear how outdated especially consumer electronics were in the USSR, with technologies like digital audio CDs and their players being one good point of comparison. In a recent video by a railways/retro tech YouTube channel we get a look at one of the earliest Soviet CD players.

A good overall summary of how CD technology slowly developed in the Soviet Union despite limitations can be found in this 2025 article by [Artur Netsvetaev]. Soviet technology was characterized mostly by glossy announcements and promises of ‘imminent’ serial production prior to a slow fading into obscurity. Soviet engineers had come up with the Luch-001 digital audio player in 1979, using glass discs. More prototypes followed, but with no means for mass-production and Soviet bureaucracy getting in the way, these efforts died during the 1980s.

During the 1980s CD players were produced in Soviet Estonia in small batches, using Philips internals to create the Estonia LP-010. Eventually sanctions on the USSR would strangle these efforts, however. Thus it wouldn’t be until 1991 that the Vega PKD-122 would become the first mass-produced CD player, with one example featured in this video.

Continue reading “Soviet CDs And CD Players Existed, And They Were Strange” →

How A Belkin USB Charger Pulls Off A 3 Milliwatt Standby Usage

March 22, 2026 by Maya Posch 21 Comments

Belkin charger standby power. (Credit: Denki Otaku, YouTube)

A well-known property of wall warts like power bricks and USB chargers is that they always consume some amount of power even when there’s no connected device drawing power from them. This feels rather wasteful when you have a gaggle of USB chargers constantly plugged in, especially on a nation-sized scale. This is where a new USB-C wall charger by Belkin, the BoostCharger Pro, is interesting, as it claims ‘zero standby power’, which sounds pretty boastful and rather suspect. Fortunately, [Denki Otaku] saw fit to put one to the test and even tear one down to inspect the work of Belkin’s engineers.

Naturally, no laws of physics were harmed in the construction of the device, as ‘zero standby power’ translated from marketing speak simply means ‘very low standby power usage’, or about 3 milliwatt with 0.3 mA at the applied 100 VAC.

Fascinatingly, plugging in an e-marker equipped USB-C cable with no device on the other end caused this standby usage to increase to about 30 mW, clearly disabling the ‘zero standby’ feature. With that detail noted, it was time to tear down the charger, revealing its four PCBs.

Continue reading “How A Belkin USB Charger Pulls Off A 3 Milliwatt Standby Usage” →

Studying A Battle Born LFP Battery’s Death Under Controlled Conditions

March 19, 2026 by Maya Posch 30 Comments

The test setup for the Battle Born LFP cycling. (Credit: Will Prowse, YouTube)

There has been quite a bit of news recently about the Battle Born LiFePO₄ (LFP) batteries and how they are dying in droves if not outright melting their plastic enclosures. Although the subsequent autopsies show molten plastic spacers on the bus bars and discolored metal in addition to very loose wiring, it can be educational to see exactly what is happening during repeated charge-discharge cycles at a fraction of the battery’s rated current. Thus [Will Prowse] recently sacrificed another Battle Born 75 Ah LFP battery to the Engineering QA Gods.

This time around the battery was hooked up to test equipment to fully graph out the charging and discharging voltage and current as it was put through its paces. To keep the battery as happy as possible it was charged and discharged at a mere 49A, well below its rated 100A.

Despite this, even after a mere 14 cycles the battery’s BMS would repeatedly disconnect the battery, as recorded by the instruments. Clearly something wasn’t happy inside the battery at this point, but the decision was made to push it a little bit harder while still staying well below the rated current.

Continue reading “Studying A Battle Born LFP Battery’s Death Under Controlled Conditions” →

Teardown Of A 2026 LEGO SMART Brick

March 18, 2026 by Maya Posch 44 Comments

LEGO SMART brick from its side. (Credit: EvilmonkeyzDesignz, YouTube)

At the beginning of March this year LEGO released their new SMART brick, which looks like a 2×4 stud brick and is filled to the brim with sensors, LEDs, NFC and Bluetooth functionality, as well as a purported custom ASIC. The central idea behind it appears to be to add a lot of interactivity to LEGO builds while allowing for mesh-style communication with other SMART bricks. Naturally, this makes it a great subject for a teardown, which is what [EvilmonkeyzDesignz] over on YouTube did in a recent video.

Normally the only way you can purchase one of these new bricks is by buying them as part of a ‘Smart Play’ set, but someone was selling singular bricks on EBay. As the brick is inductively recharged, it’s pretty well-sealed, requiring a fairly destructive opening method.

Directly below the transparent top is a speaker, with the opposing PCB on the main body containing a microphone as well as a number of RGB LEDs. On the opposite side of this PCB we find the photo sensor, but to get to this part of the PCB the copper wires that wrap around the entire main assembly have to be disconnected from the PCB’s side pads with some force as they’re apparently pressed in place without the use of solder.

Continue reading “Teardown Of A 2026 LEGO SMART Brick” →

A Look Inside The Creative MB-10 MIDI Blaster

March 3, 2026 by Maya Posch 16 Comments

Before it became viable to distribute and play music tracks on home computers, the use of FM and Wavetable synthesis was very common, with MIDI Wavetable-based devices like the Roland MT-32 and SC-55 still highly sought after today. The Creative Midi Blaster MB-10 that [Yeo Kheng Meng] reviewed and tore down for an analysis isn’t quite as famous or sought after, but it provides a good example of what Creative Labs was doing at the time in this space.

Released in 1993, it definitely has more of a popular style vibe to it than the utilitarian Roland devices, even if this means highly impractical curves. In the list of features it claims Roland MT-32 emulation, which would have made it quite a bit more useful to the average user, including gamers of the era. Games like DOOM supported these MIDI devices for audio, for example.

In terms of price only the Roland SC-55ST comes close to the MB-10, similarly dropping a screen and a host of features. In terms of features the MB-10 claims far fewer instruments than the SC-55 variants, with even with the slightly higher priced SC-55ST massively outgunning it in raw specs. So would you ever buy the MB-10 back then and consider it a ‘good deal’? If $100 in 1990s money was worth losing full MIDI compatibility for, then it seems the answer was ‘yes’.

Continue reading “A Look Inside The Creative MB-10 MIDI Blaster” →

Teardown Of Dangerous Fake Wago Connectors

March 1, 2026 by Maya Posch 31 Comments

Everyone loves Wago connectors for how versatile and effective they are for quickly and securely connecting conductors, but it can be tempting to buy a bag of the significantly cheaper knock-offs. The reason why this can be a terrible idea is explained by [Big Clive] who tore down a few bags of them to ogle at their internals.

The main problem with some of these knock-offs is the way that they use the plastic molding as part of the structure that holds the conductors in place. Over time this plastic will develop larger tolerances, with heat developed from passing large currents speeding up the process. As the examined type of connector relies on metal clamps that securely push the conductor onto the busbar, having the plastic weaken, and the clamp correspondingly loosen up, is clearly not a desirable scenario.

As [Clive] says in the video, you’re probably okay using these cheapo knock-offs for a quick test on the bench, but you should never put them in a permanent installation. Not just due to potential fiery scenarios, but also for insurance claims should the worst come to pass, and the insurance company finds dodgy connectors everywhere in the electrical wiring. This isn’t the first we’ve heard of knock-off Wago problems.

Continue reading “Teardown Of Dangerous Fake Wago Connectors” →