Anker Prime 26250 (300W): our full review

An external battery pack rated at 99.75 Wh (26250 mAh) with 140 W available on each USB-C port, a figure that actually holds up over standard USB-C with a cable rated for 5 A, without the proprietary lock already found on the Anker 737 Power Bank. Real-world efficiency falls between 80 and 90 % of the rated capacity. The measured weight, around 577 to 580 g, comes in under the 600 g listed on the spec sheet. Recharging the battery pack itself, rated at 1 hour and 13 minutes with a 250 W input, turns out faster in practice than that figure, between 46 and 59 minutes depending on the charger used.

Our rating
4.1/5
Capacity and runtime: 4.0 out of 5 (weighting 25%)Capacity4.0Output power: 4.2 out of 5 (weighting 20%)Power4.2Size and weight: 4.1 out of 5 (weighting 20%)Size4.1Ports and cables: 3.8 out of 5 (weighting 15%)Ports3.8Recharging: 4.4 out of 5 (weighting 10%)Recharging4.4Build and endurance: 3.9 out of 5 (weighting 10%)Build3.9
Anker Prime 26250 (300W) external battery on a light background

The essentials

Unlike the Anker 737 Power Bank already reviewed on this site, where the advertised 140 W per port never checked out above 90 to 93 W over direct USB-C, the Prime 26250 delivers on its promise: the actual draw comes in close to 140 W over standard USB-C, provided the connected device can request that much and the cable is rated for at least 5 A. Recharging the battery pack itself turns out even faster than the manufacturer's own figure. The actual weight, around 577 to 580 g, also comes in under the number listed on the spec sheet. Real-world energy efficiency (80 to 90 %), however, stays close to that of the previous generation, with no clear improvement despite the input being raised to 250 W. The PowerIQ 4.0 and ActiveShield 4.0 technologies the manufacturer promotes have not been independently verified to date. No recall affects the Prime lineup, unlike several other Anker lineups recalled in 2025.

Strengths

  • The 140 W per port figure is genuinely reachable over standard USB-C, with no proprietary lock, unlike the Anker 737 already published on this site
  • Battery pack recharge faster in practice than the manufacturer's figure: 46 to 59 minutes measured against 1 hour and 13 minutes announced
  • Actual measured weight below the official figure: around 577 to 580 g against 600 g listed
  • Capacity near the top of what is allowed in airplane cabins (99.75 Wh), just under the 100 Wh threshold
  • No recall affects the Prime lineup, unlike several other Anker lineups recalled in 2025
  • Colour screen and a dedicated app for tracking charge status in real time

Limitations

  • Real-world energy efficiency (80 to 90 %) close to that of the previous generation, with no clear improvement despite the input being raised to 250 W
  • PowerIQ 4.0 and ActiveShield 4.0, heavily promoted by the manufacturer, remain unverified by any independent measurement to date
  • USB-A port limited to 22.5 W in isolation, dropping to 20 W when both USB-C ports are drawing full power
  • The firmware does not support Adaptive Voltage Scaling (AVS), a USB Power Delivery feature offered by some high-end rival chargers
  • Actually reaching 140 W requires a receiving device capable of requesting it and a cable certified for at least 5 A, two conditions that are not always both met
  • No independent measurement has clocked whether the 140 W draw holds up for the full length of an intensive work session
Anker Prime 26250 (300W): see the full details and price →

140 W per port: genuinely reachable, no proprietary lock

The question is worth asking directly, given the precedent set by the Anker 737 Power Bank already reviewed on this site: is the advertised 140 W per port genuinely reachable, or only under unspecified restrictive conditions? On the Prime 26250, the answer differs from the 737's. The 737 never exceeded 90 to 93 W over direct USB-C, with the 140 W figure only reachable using a 16-inch MacBook Pro over a proprietary MagSafe cable. The Prime 26250 has no MagSafe port at all: everything runs over standard USB-C PD 3.1 / PPS, and the actual draw holds steady close to 140 W with a MacBook Pro connected over plain USB-C.

The real nuance, then, is not a hidden proprietary lock but two ordinary conditions of the USB-C PD standard: a receiving device capable of genuinely requesting 140 W (a high-end 16-inch MacBook Pro or a handful of gaming laptops, not a smartphone or a compact laptop), and a cable certified for at least 5 A. A device that does not request 140 W, such as a 14-inch MacBook Pro with a smaller battery or a smartphone, will naturally not draw more than it needs, which is not a limitation of the product itself.

No independent measurement has clocked whether the 140 W draw holds up for the full length of an intensive work session (video editing, code compiling), the equivalent of the test that revealed the 737's real ceiling: the claim holds up for a short, one-off charge, not yet for a long, sustained one.

Recharging the battery pack itself: faster in practice than advertised

The manufacturer rates a full recharge at around 1 hour and 13 minutes with both USB-C ports drawing power at the same time, up to 250 W input. In practice, the actual recharge time is faster than that figure: 46 minutes with two 140 W chargers, 55 minutes with a single 150 W charger, 59 minutes with a single 140 W charger. Reaching 50 % takes 13 to 15 minutes. The combined measured input power across both USB-C ports reaches 238 to 246 W, close to the advertised 250 W ceiling without quite reaching it.

That is a fairly rare situation: most marketing claims in this category tend to be optimistic next to the real-world figure. Here, the measured full recharge time under good conditions beats the official number.

80 to 90 % real-world efficiency, no clear improvement over the previous generation

Out of the 99.75 Wh advertised, the energy actually delivered, measured across several full charge cycles, falls between 79.6 and 89.8 Wh, or 80 to 90 % real-world efficiency. That is in the same range already measured on the Anker Prime 20000 (200 W), the previous generation in the same lineup: 82 % measured efficiency with a dedicated instrument (70.72 Wh consumed on input for 58.18 Wh delivered on output). Despite the charging input being raised from 100 to 250 W and the per-port output raised from 100 to 140 W, overall energy efficiency therefore does not improve much from one generation to the next.

An actual measured weight under the advertised 600 g

The official spec sheet lists around 600 g. The measured weight comes in lower, between 577 and 580 g, with dimensions of around 160 x 63 x 38 mm. The difference, on the order of 3 to 4 %, is minor and works in the buyer's favour: it is one of the rare cases in this review where the measured reality is more favourable than the manufacturer's figure rather than the other way around.

Safety: the Prime lineup left out of every Anker recall in 2024 and 2025

Anker has issued several external battery recalls in 2024 and 2025: a recall in June 2025 covering around 1.15 million units of the PowerCore 10000, and a recall in September 2025 covering around 481000 units across five references in the Power Bank 10K, MagGo, and Zolo lineups, over a risk of overheating or fire. The manufacturer's official recall page lists these exact references and makes no mention at any point of the Prime lineup or the Prime 26250 model. No recall specific to this model has otherwise been identified.

This is based on an absence across every available list rather than an explicit manufacturer statement excluding the Prime lineup: it is a strong signal, not a formal guarantee. No report of failure, overheating, or a hardware defect has otherwise been identified for this specific model either, still a cautious judgment for a device on the market only since November 2025.

Against the Prime 20000 (200W): a real gain, but concentrated on power

Anker Prime 26250 (300W) against the Prime 20000 (200W)
CriterionPrime 26250Prime 20000
Capacity99.75 Wh72 Wh
Power per USB-C port140 W100 W
Total power300 W200 W
Charging input250 W100 W
Measured real-world efficiency80 to 90 %82 %
Weight577 to 580 g measured544 g measured

The generational progress is real but concentrated on available power (140 W against 100 W per port, measured on both sides) and on how fast the pack itself recharges, thanks to the input being raised from 100 to 250 W. Energy efficiency, by contrast, stays flat around 80 to 90 %, and weight naturally increases with the extra capacity on board. Both generations also share similar thermal safety behaviour, with power reduced under sustained full-power load, a sign of a consistent protection policy rather than a radical change.

PowerIQ 4.0 and ActiveShield 4.0: marketing names not independently verified

According to the manufacturer's documentation, PowerIQ 4.0 refers to dynamic power redistribution between ports based on each connected device's needs, re-evaluated roughly every 3 minutes, on top of PD 3.1 and PPS support up to 140 W. ActiveShield 4.0 refers to temperature monitoring claimed at 120 times per second. No independent, quantified measurement can confirm to date a real gain from these technologies over the previous generation (PowerIQ 3.0): these are feature names documented by the manufacturer, not results verified by a third party.

One concrete, independent technical nuance did stand out, however: the current firmware does not support Adaptive Voltage Scaling (AVS), a USB Power Delivery standard feature offered by some high-end rival chargers. That is a technical detail absent from the marketing pitch.

The USB-A port, secondary next to the two USB-C ports

The secondary USB-A port delivers 22.5 W when used on its own. When both USB-C ports are drawing full power at the same time, its actual output drops to around 20 W. This is consistent with the advertised 300 W total spread across the three ports, but a useful reminder that the USB-A port is not given priority in that split.

99.75 Wh: just under the cabin limit, but not without friction

The 26250 mAh capacity was calculated to stay under the 100 Wh threshold beyond which most airlines ban external batteries from the cabin (26250 mAh at a nominal voltage of 3.8 V works out to 99.75 Wh). This calculation complies with current regulations, but the unit's imposing size can still draw questions from security staff at the checkpoint, despite its legal compliance.

Who it suits, and who it does not

It suits anyone with a laptop genuinely capable of drawing 140 W (a high-end 16-inch MacBook Pro in particular) who wants fast top-up charging for it, along with a capacity close to the maximum allowed in an airplane cabin.

It does not suit anyone looking above all for a gain in energy efficiency over an entry-level model from the same brand, since real-world efficiency stays close to that of the previous generation despite the higher price, nor anyone who only needs to charge a smartphone, for which the 140 W per port makes no real difference.

The product and its alternatives

Anker Prime 26250 (300W)

Anker Prime 26250 (300W)

See price (4)

26,250 mAh and 300 W of total output: two USB-C ports at 140 W that charge a MacBook Pro like mains power, and 250 W recharging that refills the pack before your eyes.

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Frequently asked questions

Yes, unlike the 737. The actual draw comes in close to 140 W over standard USB-C, with no MagSafe-style proprietary lock, provided the device can request it and the cable is certified for 5 A.

The manufacturer rates it at 1 hour and 13 minutes. The actual recharge time is faster, between 46 and 59 minutes depending on the charger used, with 50 % reached in 13 to 15 minutes.

No. The 2024 and 2025 Anker recalls cover the PowerCore, MagGo, and Zolo lineups. The official recall page mentions neither the Prime lineup nor this model.

Around 577 to 580 g measured, a little under the 600 g listed on the official spec sheet.

The rating in detail

Our rating
4.1/5
Capacity and runtime 4.0
Output power 4.2
Size and weight 4.1
Ports and cables 3.8
Recharging 4.4
Build and endurance 3.9
Anker Prime 26250 (300W): see the full details and price →