Secret Scotland

If it's secret, and in Scotland…

Lidl technical problems 1 – Rechargeable batteries

A few years ago I was involved in a project that involved working with a tech-type (from the south coast of England) who had similar interests to my own, and one of the things we exchanged notes on was hardware purchased from Lidl. He’d been buying their stuff for a few years, but I had only started, however, he warned me not to expect too much. He’d been let down quite a bit, and further suggested I take their guarantee with a pinch of salt. The problem he found was that by the time something failed, it was off the shelves, and it took forever to get someone to deal with any problems as the items are produced all over Europe, not the UK.

Sad to say, a few years down the road we are no longer in touch, but his warnings have come true, and I think it’s time to mention them.

Rechargeable batteries and the PP3 in particular

I’ve used a few of their rechargeable batteries (all NiMH) in various applications, and they work ok at first, but don’t seem to last.

I replaced a pair of AA cells fitted inside a shaver, and they barely lasted a year. The original cells lasted 10 years before they needed to be replaced, and failed gradually. The replacements started to fail after 10 months, and within a few weeks would not even hold charge past one shave. No fun, since renewal means complete dismantling of the unit to reach them. Now, I can only use the shaver when plugged in to the mains – although the display says I have 34 shaves in reserve.

The same cells seem to have lasted longer in things like cameras, but their use is different, so may suit them better.

By comparison, similar AA and AAA cells from Maplin are still working like new after 5 years and more.

The worst example was a Lidl PP3. This is a battery I try to avoid (for its short life and high cost) but this is not always possible.

The first sign that there was going to be a problem was when it would not charge or operate the equipment it was fitted to – a symptom that appeared after only a few months.

Eventually I noticed that the negative terminal was discoloured, and closer inspection showed it to be coated with a non-conductive layer of black corrosion. Scraping this off restored operation temporarily, but the contamination simply returned, and had to be removed repeatedly. Eventually the corrosion caused some of the bent metal spring contacts to break/fall off, rendering the contact unreliable. This was not really relevant – by that time, the battery was no longer working anyway. The state of the negative terminal can be seen in the first pic below. This also shows the presence of liquid which had been leaking from the individual cells used to make up the battery, and had been inside the casing:

Corroded negative terminal

Corroded negative terminal

The next pic shows the condition of the cells found inside the casing.

All are corroded, no doubt caused by whatever liquid has been leaking from them:

Corroded PP3 interior

Corroded PP3 interior

While it seems that they vent hydrogen and water if overcharged, with no seriously toxic materials involved, I still noted that the liquid was oily, and never evaporated as water would have. Unlike AA or AAA, PP3 rechargeables are generally charged on time only, while the others can have a full charge detected, which stops the charging automatically.

I never charge a PP3 until it has been fully discharged in service.

For comparison, While the above battery failed to last for even a year, the one below was purchased around 2000, and is still in constant use to this day. The other one was bought to stand in for it when it was being charged!

RS PP3 about 15 years old

RS PP3 about 15 years old – and still going strong

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April 14, 2015 - Posted by | Uncategorized | , , ,

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