Rechargeable desk lamps: cordless and portable compared

When a cordless desk lamp makes sense

The search term “cordless desk lamp” combines two expectations. One is a bright task light that works without a mains cable. The other is a small, movable lamp that sits where no socket happens to be within reach. Most rechargeable models meet the second expectation. When reading in bed, at a bunk bed in a child’s room, on a balcony table or at a dining table that becomes a study spot in the evening, that is a real advantage.

So start with the task. If you spend many hours a day at a screen, you need light that stays constant and sufficiently bright and does not need recharging after a few hours. A mains-powered lamp from the desk lamps category is the more reliable solution for that. A rechargeable lamp is better seen as a second light at the workplace: at the notepad, at a study spot, for short jobs or when travelling.

Mounting is another point. Without a cable there is nothing to trip over, and the lamp can be moved in seconds. In return there is no fixed position and often no adjustable arm. Clamp models grip the edge but need a suitable tabletop thickness. Standing models take up surface area, which is scarce on small tables. You can work out which type suits your space with the lighting calculator, which brings together room, task and lighting need.

Reading battery, run time and charging method correctly

Battery capacity is given in milliampere hours. On its own this figure says little, because run time only follows from the energy in the battery divided by the power consumption of the chosen brightness setting. A battery with a nominal voltage of 3.7 volts and 3,600 milliampere hours stores roughly 13.3 watt hours in theory. At 6 watts of power that gives a good two hours, and a multiple of that at a low dimming setting.

This very calculation shows why run time advertising with large hour counts should be read with caution. For the One Fire WH-C17 rechargeable lamp, the listing states up to 200 hours, which can at most refer to the dimmest setting. Calculated with the listing’s own figures, about two hours remain at full brightness. For the ZAPLIT rechargeable clamp lamp too, the advertised ratio of 35 hours on the lowest setting to 5 hours on the highest does not fit the stated capacity of 2,000 milliampere hours together with the stated power. There is no manufacturer document that clarifies this for either model.

Also look at the charging method. The Suright LD121 rechargeable table lamp charges via USB, but according to the listing a power adaptor is not included, only a cable. The ZAPLIT uses USB-C and, according to the listing, can be charged from a power bank, laptop or adaptor. For the PreeOtti rechargeable table lamp with touch dimmer, no source for this specific model states the connector type or charging time. So if you charge on the move you need your own USB source, and if you plan to use the lamp as an emergency light in the evening, you should know beforehand how it behaves when the battery is low. The listings say nothing about this.

How much light a rechargeable lamp delivers

Light output is rarely stated in full in the documents for rechargeable lamps. For the ReinHoo rechargeable clamp lamp for beds the listing states 450 lumens, and for the One Fire WH-C17 rechargeable lamp 300 lumens at 4,000 kelvin and 6 watts. Both figures come only from the listing text, and there is no manufacturer document or measuring distance for either model. For the PreeOtti rechargeable table lamp with touch dimmer and the ZAPLIT no luminous flux is given at all, and for the ZAPLIT lamp a kelvin value is missing as well.

How much luminous flux makes sense for a desk task is explained on the page about lumens for desk lamps. The number alone is not enough anyway, because beam angle, distance to the work surface and glare decide how much light actually falls on a book or notepad. A broadly diffusing table lamp with a shade spreads the light into the room, while a gooseneck concentrates it on a small area. This fits the fact that rechargeable models are, in everyday use, more reading and mood lights than a replacement for a task lamp.

For colour temperature the following applies: warm white light around 3,000 kelvin feels calmer in the evening, while cool white light around 6,000 kelvin is usual for concentrated tasks. The basics are covered under colour temperature and kelvin. According to the listing, the Suright offers 3,000, 4,500 and 6,000 kelvin, and the ReinHoo, according to the listing, five tones from 3,000 to 6,500 kelvin. The lumens to watts chart helps to put wattage figures in context.

Clamp, base or foldable: the design decides

The design determines where a rechargeable lamp is usable. Clamp lamps save surface area and can be aimed using the gooseneck. According to the listing, the ReinHoo clamp grips up to a maximum of 5 centimetres, and the gooseneck is given as 30 centimetres. According to the listing, the ZAPLIT has a clamp opening of 6 centimetres and a 40 centimetre gooseneck. Measure your table edge before you order, as thicker tops will not fit.

Foldable and standing models do not need an edge. According to the listing, the Suright is foldable and fits into a rucksack when folded. The manufacturer’s packaging template only confirms the model designation LD121-WH and the packaging dimensions of 71 by 63 by 166 millimetres, nothing more. The One Fire is given as 16 by 16 by 7 centimetres and is considerably smaller when folded. The PreeOtti is a table lamp with a shade and, according to the listing, has IP54 protection.

According to BS EN 60529, this IP rating means protection against dust in harmful quantities and against splashing water from all directions. In the spray area of a shower or when immersed, it is not sufficient. On the edge of a washbasin, a windowsill or a balcony table it is adequate. The word “shower lamp” in a listing should not tempt you to place the lamp in the spray zone.

The models compared

The table summarises what the respective product pages say. All values are details from listings, and there is no manufacturer document with measurement data in any case. Entries such as “no information” mean that no source states the value. There are no measurements of our own and no documented hands-on testing for any of the models.

What this means for reading: if you need focused light on a book in bed or at an edge, the two clamp models offer the right design. If you want a small travel light, look at the foldable models. If you would rather have mood lighting on a bedside table or balcony, the shade lamp is the right choice. For hours of screen work, these documents do not support any of the models.

Which design suits whom

For a bed or a bunk bed, a clamp lamp such as the ReinHoo suits, provided the edge is no thicker than 5 centimetres. It keeps the bedside table free and can be aimed using the neck. For a study spot at a kitchen or dining table that has to be cleared again in the evening, a foldable lamp such as the Suright is an obvious choice. As an alternative to a fixed desk lamp it works for short jobs. The same applies to the One Fire, which according to our assessment is intended for short-term reading light in changing places and not as a permanent workplace lamp.

If you need pinpoint light at a shelf, a music stand or a bed frame, you can consider the ZAPLIT, but you should allow for the unclear run time and the missing luminous flux. For a bedside table, balcony or dining table without a socket, the PreeOtti suits, whose shade spreads the light over an area instead of focusing it. It does not replace a task lamp for the desk.

If children use the lamp, the cordless principle has one advantage: there is no cable to pull on. It does not replace checking the charging method, and a USB power adaptor then belongs in adult hands. Before buying, it is also worth checking against the variant in the listing, because colour, size and set can differ within the same listing, and the details with them.

Buying decision: checks before ordering

Before you order a rechargeable lamp, a short checklist helps. First: decide how long you need light at a stretch, and work out the run time yourself from capacity and power. Second: measure the edge, the footprint and the distance to the work surface. Third: find out how the lamp is charged and whether a power adaptor is included. Fourth: note which figures in the listing are only advertising claims and which are supported by a manufacturer document.

For the models named here, a manufacturer document supports something only in the case of the Suright, and that is the model designation and packaging dimensions. All other details come from listing texts. This is not a verdict on the devices, but it explains why we do not present anything as measured. We did not have any of the models in hand, and no hands-on testing is documented. If you want more room for manoeuvre on brightness and adjustment range, also look at the desk lamps category, where mains-powered models with focused task light are also listed.