XTAR C CLR 7200 Review: USB-C Rechargeable C Batteries Bring an Old Maglite Back to Life

Rechargeable batteries are about as unexciting as it gets. Rechargeable C cells though, are a little more interesting. Particularly the XTAR C CLR 7200, which promises a constant 1.5-volt output and charges directly over USB-C.

Don’t let the 7200 mislead you. The XTAR has a stated output capacity of 4350 mAh, with a lithium-ion cell internally, coupled with circuitry that provides a regulated 1.5V output. The 7200 refers to the mWh.

When they approached me, I had to think hard about what I own that still uses C cells. As luck would have it, I had what seemed like two ideal test subjects that would bookend the use cases.

 

Old Maglite, new XTAR rechargeable C batteries

The first test subject is the classic Maglite – with the big black aluminium body, adjustable beam and an actual incandescent globe rather than an LED.

I have had this beautiful beast for over three decades, and it carries a lot of fond memories. It was the torch I carried when I worked on the flightline at the old Kai Tak Airport at HKG. It bears the scars of constant usage, surviving a roughly 11-metre fall to the tarmac from the Auxiliary Power Unit (APU) area of a 747-400 when I was changing the aircraft’s APU battery (no lithium-ion back then!). To give some perspective on that fall, the APU on a 747 sits inside the very end of the tail.

Three C cells sit end-to-end inside the handle, giving the torch a nominal 4.5V supply. Traditionally, that meant alkaline batteries.

The problem with alkaline cells isn’t simply that they’re disposable. Their voltage also declines progressively as they’re discharged. An incandescent torch makes that particularly obvious: the beam gets dimmer and yellower as the batteries run down.

I know that just too well because I would change batteries once or twice each shift back in the day.

The XTARs behave differently.

Each C CLR 7200 supplies a regulated 1.5V, so three of them provide approximately 4.5V to the Maglite. More importantly, they’re designed to maintain that voltage for most of their discharge cycle rather than following the steadily declining voltage curve of an alkaline battery.

And an old incandescent torch is a surprisingly good way to see the difference.

 

On the flip side: testing a low-drain flip clock

Here, I have paid the dad joke price now.

I also have a proper mechanical split-flap clock, which Shokz gave me as a Christmas present. I initially thought it would make the perfect low-drain second test for the XTAR C CLR 7200.

There was just one small problem: when I opened it up, I discovered it actually runs on a single D cell.

So much for that idea.

The mechanism uses a small motor and gear train to advance the cards, with no display illumination consuming power continuously. It would have been an interesting test of the XTAR’s performance in an extremely low-drain device — just not with a C cell.

I would expect it to be the sort of device where you could realistically leave a battery installed untouched for a very long time.

 

XTAR C CLR 7200 capacity: what does 4350mAh actually mean?

Reading battery capacities can get confusing when different chemistries are involved.

XTAR rates each C CLR 7200 at 4350mAh and 7200mWh, or 7.2Wh. Watt-hours are generally the more useful figure when comparing the actual energy available from batteries using different chemistries and internal voltages.

With three cells in the Maglite, that’s a nominal 21.6Wh of rated energy. Because the cells are connected in series, however, you don’t simply add their milliamp-hour ratings together and call the pack 13,050mAh.

That’s an important distinction if you’re looking at the specifications and wondering how these compare with alkaline C cells that can carry considerably larger-looking mAh figures.

XTAR C CLR 7200 vs alkaline C batteries

A good alkaline C cell can store more total energy than the XTAR, particularly when discharged slowly.

That means the C CLR 7200 isn’t necessarily going to beat a quality alkaline battery on absolute runtime in every device.

But runtime isn’t the whole story.

An alkaline battery’s quoted capacity is highly dependent on how it’s discharged, and much of that capacity is delivered after its voltage has already fallen substantially. That may be acceptable for some electronics, but it’s immediately visible with an incandescent bulb.

The XTAR takes almost the opposite approach: less total capacity than the best alkaline C cells, but a regulated output that keeps the voltage around 1.5V.

In the Maglite, that means the torch should spend considerably more of its runtime operating as though it has fresh batteries installed.

Incandescent bulbs present one complication

An incandescent bulb isn’t the easiest load for an electronically regulated rechargeable battery.

When the filament is cold, its resistance is much lower than it is once glowing. Switching the torch on therefore produces a brief current surge substantially higher than its normal operating current.

The C CLR 7200 contains protection and voltage-regulation electronics, so there’s theoretically the possibility of that startup current tripping the battery’s protection circuit.

In practice, the Maglite switched on normally and remains illuminated, which means the batteries are evidently tolerating the initial surge.

It’s something worth considering if you’re buying these specifically for old incandescent equipment, though. A C battery fitting physically and producing 1.5V doesn’t automatically mean every electronically regulated rechargeable will behave identically to an alkaline cell under every load.

USB-C charging changes the equation

The big advantage here is convenience.

Each XTAR battery has its own USB-C charging port. There’s no dedicated C-cell charger required and no need to find space for another bulky charger that might spend most of its life in a drawer.

Plug the batteries into USB-C, recharge them and put them back in the torch. XTAR has provided a USB-A to dual-headed USB-C cable for each set of XTAR C CLR 7200 batteries.

A full recharge takes around three hours.

That makes considerably more sense for something like an old Maglite that may only see occasional use.

There’s another advantage, too: no forgotten alkaline batteries sitting inside an aluminium torch for years.

Anyone who has opened an old torch, radio or toy to discover leaking alkaline cells – and the resulting corrosion – will understand the appeal immediately.

Regulated 1.5V changes the discharge experience

There is a trade-off to regulated lithium rechargeables.

Alkalines provide plenty of warning that they’re approaching the end of their useful life. The Maglite slowly becomes dimmer, and eventually you realise it’s time for new batteries.

The XTARs don’t behave that way.

Because their electronics are maintaining the output voltage, the torch remains relatively bright until the batteries are close to exhausted. At that point, protection circuitry will eventually shut the output down.

So instead of: bright → dimmer → yellow → barely glowing → dead, the experience is closer to: bright → bright → bright → dead

Reminds me of “one tequila, two tequila, three tequila, floor!”

That’s arguably better while you’re actually using the torch, but it also means you don’t get the visual warning that comes with an alkaline-powered incandescent torch.

A surprisingly good match for old technology

Putting USB-C rechargeable lithium batteries into a decades-old incandescent Maglite feels slightly absurd.

It also makes a lot of sense.

The XTAR C CLR 7200 doesn’t transform an old Maglite into a modern high-output LED torch. Nor should it. Modern LED flashlights are vastly more efficient, smaller and capable of producing dramatically more light.

Instead, the XTARs address one of the least appealing parts of owning older battery-powered equipment: continually buying disposable cells for something you only use occasionally.

They’re particularly interesting in an incandescent Maglite because the regulated 1.5V output plays directly to one of the weaknesses of alkaline batteries. Rather than watching the beam gradually fade as battery voltage declines, the old bulb gets something much closer to its intended supply voltage for most of the charge.

There are caveats. The 4350mAh specification isn’t directly comparable with the headline capacities quoted for alkaline C cells.

I ran the XTAR C CLR 7200 flat several times with the Maglite left on. Runtime was a little shorter than I remember getting from fresh alkaline C cells, although I didn’t have a matched set of alkalines on hand for a controlled back-to-back comparison.

For other devices, electronically regulated batteries can behave differently with unusual or high-current loads.

But there’s something satisfying about taking an old torch designed when disposable alkaline batteries were simply assumed and making it rechargeable without modifying the torch at all.

Three batteries out. Three USB-C rechargeable batteries in. My beloved Maglite remains exactly what it always was, scars and all, but with a modern power source. No more alkalines.

And yes, I know I could upgrade the Maglite with an LED module. But I won’t. This beast is my time capsule.

As for the Shokz clock, it turns out XTAR has an answer for my mistake too. The company sells a similar USB-C rechargeable D cell with a regulated 1.5V output, rated at 7400mWh.

The XTAR C CLR 7200 has an RRP of US$9.90 per pair, with a USB-A to dual-head USB-C charging cable included.

DRN would like to thank XTAR for providing the review units.