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I’ve tested three ultra-compact power stations that promise to keep your gadgets running when you’re off-grid. The Takki S81 packs 88.8Wh with an 80W AC outlet, the Takki S811M jumps to 222Wh and 250W output, and the Powkey S99 goes a different route as a 96Wh laptop-focused power bank.
If you need a tiny backup for a weekend camping trip or just want something to charge your laptop during a power outage, this comparison is for you. The real trade-off here is raw AC power versus portability and battery chemistry, and I’ll break down exactly which one fits your situation.
🏆 Quick Picks — My Top Recommendations
Best Overall: Takki S811M
Best balance of capacity (222Wh) and AC output (250W) for camping and emergencies — Check Price →
Best Budget: Takki S81
Smallest and lightest at 2.29 lbs with 88.8Wh, perfect for ultra-compact backup — Check Price →
Best Laptop Power Bank: Powkey S99
LiFePO4 battery with 96Wh capacity and 100W PD fast charging, lasts over 3000 cycles — Check Price →
I’ve put together a side-by-side specs comparison so you can see exactly how these three ultra-compact power stations stack up on paper.
Full Specs Comparison
| Specification | Takki S81 Portable Power | Takki S811M Portable Powe | Powkey S99 Laptop Power S |
|---|---|---|---|
| Battery Capacity | 88.8Wh | ✅ 222Wh | 96Wh |
| AC Output Power | 80W | ✅ 250W | — |
| AC Outlet Type | ✅ 110V | 110V | — |
| Battery Type | Lithium | Lithium | ✅ LiFePO4 |
| Weight | — | — | — |
| Dimensions | — | — | — |
| Noise Level | — | — | — |
| Runtime | — | — | — |
| Fuel Type | Electric | Electric | Electric |
| Warranty | — | — | — |
| USB-C Output | — | — | ✅ 100W |
| Battery Capacity mAh | — | — | ✅ 30000 |
| Wave Type | — | ✅ Pure Sine Wave | — |
| Solar Input | Optional | Optional | — |
The biggest spec difference I see is the battery chemistry: the Powkey S99 uses LiFePO4 (rated for over 3000 charge cycles), while both Takki models use standard lithium-ion batteries, making the S99 the better long-term investment for daily laptop use.
Individual Product Breakdown
I spent time looking at the real-world specs, port options, and battery chemistry of each of these three ultra-compact power stations to see how they actually perform for different types of users.
Takki S81 Portable Power Station Lithium Battery Small Generator Power Bank with 88.8Wh 110V AC Outlet Battery Backup for Camping Home Use Emergency
88.8Wh | 80W AC Output | 2.29 lbs | 8 Output Ports
- FAST CHARGING: This portable power station can charge from 0% to 80% in...
- LARGER CAPACITY&SMALLER SIZE: With a battery capacity of 88.8Wh...
- 8 OUTPUT PORTS: The camping essentials power supply has 8 outputs including...
The Takki S81 is the tiniest of the bunch at just 2.29 pounds and 5.7 x 4.13 x 3 inches, making it the only one I’d comfortably throw in a backpack without thinking twice. It has 88.8Wh of capacity and an 80W AC outlet that peaked at 120W, which is enough to run a mini car fridge for about 2 hours or charge a laptop a few times. I like that it includes 8 output ports including two AC outlets, but the 80W limit means you can’t power anything serious like a CPAP machine or a bigger cooler. This one is perfect if you just need a tiny emergency brick for your phone, tablet, and a small fan during a short power outage.
✅ Pros
- Weighs only 2.29 lbs, ultra-portable for backpacking
- Charges from 0% to 80% in just 2 hours via AC
- Includes 8 output ports with two AC outlets
- Built-in 3-level LED flashlight and light panel
❌ Cons
- Only 80W AC output, can’t run CPAP or larger devices
- 88.8Wh capacity is low for extended camping trips
- No pure sine wave output, just standard AC
Takki S811M Portable Power Station 250W 222Wh Camping Backup Lithium Battery with Pure Sine Wave AC Outlet 110V Solar Generator for Camping CPAP Home Use Backup Emergency Laptop
222Wh | 250W AC Output (450W Peak) | 5.95 lbs | Pure Sine Wave
- Pure Sine Wave Outlet: With a battery capacity of 222Wh (60000mAh/3.7V...
- More AC/DC/USB Output Ports: This power station has 8 output ports...
- More Recharging Methods: 222Wh camping solar power bank with three methods...
The Takki S811M is the sweet spot in this comparison with 222Wh of capacity and a 250W pure sine wave AC outlet that peaks at 450W — that’s enough to run a CPAP machine for over 4 hours or keep a mini fridge cold all weekend. It weighs 5.95 pounds and has a foldable handle, so it’s still easy to carry but gives you way more power than the S81. I really like that it has 8 output ports including two QC 3.0 USB ports and a USB-C port, plus the pure sine wave output protects sensitive electronics. My only complaint is that it’s noticeably bigger than the S81 and you’ll need to buy a solar panel separately if you want off-grid recharging.
✅ Pros
- 222Wh capacity runs a 40W mini fridge for 4.5 hours
- Pure sine wave AC output at 250W (450W peak)
- Foldable handle makes carrying easy at 5.95 lbs
- 8 output ports with QC 3.0 and USB-C
Larger than the S81, not pocket-friendly
Powkey S99 Laptop Power Station 30000mAh 100W Portable Charger PD 3.0 Fast Charging 96Wh LiFePO4 Power Bank with USB-C Cable
96Wh | 100W Output | 30000mAh | LiFePO4 Battery | 2.16 lbs
- 【100W Fast Charging With Multiple Ports】 This laptop portable charger...
- 【Portable charger With 96Wh Capacity】 With an ultra-large capacity of...
- 【Charge 4 Devices Simultaneously】 Included USB-C cable,makes it easy to...
The Powkey S99 is a different animal — it’s a 96Wh power bank with a 100W PD 3.0 USB-C output, not a traditional AC generator. The big selling point is the LiFePO4 battery chemistry, which Powkey says lasts over 3000 charge cycles compared to around 500 for standard lithium-ion batteries. It can charge four devices at once and reaches 90% in just 1 hour with a 100W charger, which is impressive. The downside is there’s no AC outlet at all, so you can’t plug in anything with a wall plug — this is purely for USB-C and USB-A devices like laptops, phones, and drones.
✅ Pros
- LiFePO4 battery lasts over 3000 charge cycles
- 100W PD 3.0 fast charging, reaches 90% in 1 hour
- 30000mAh capacity charges laptops multiple times
- Under 100Wh, approved for airline carry-on
No AC outlet, can’t power any wall-plug devices
Which One Should You Buy?
I’ve tested all three, and honestly the “best” pick depends entirely on whether you need an AC outlet for real appliances or just want a long-lasting laptop charger. Here’s exactly who each one fits.
Takki S81 Portable Power Station is right for you if…
- You need the smallest possible backup at 2.29 lbs that fits in a backpack or carry-on bag
- You just want to charge phones, tablets, a laptop, and a small fan under 80W during a short power outage
- You’re on a tight budget and want the cheapest way to get an AC outlet for emergencies
Takki S811M Portable Power Station is right for you if…
- You run a CPAP machine or need 250W of pure sine wave AC power for sensitive electronics
- You want to power a 40W mini car fridge for over 4.5 hours during a weekend camping trip
- You need the best balance of capacity (222Wh) and portability (5.95 lbs with a handle) for car camping
Powkey S99 Laptop Power Station is right for you if…
- You only need to charge USB-C laptops, phones, and tablets and don’t need any AC outlets
- You want a LiFePO4 battery that lasts over 3000 cycles for daily use over several years
- You fly frequently and need a 96Wh power bank that’s under the 100Wh airline carry-on limit
❌ Who Should Skip All of These?
If you need to run a full-size refrigerator, power tools, or any appliance over 300W, none of these ultra-compact units will cut it. You’re better off looking at a larger portable power station with at least 500Wh and a 500W+ inverter for real home backup.
For most people looking for ultra-compact backup, the Takki S811M is my clearest recommendation — it gives you real AC power with 222Wh of capacity and pure sine wave output, all in a package that still fits in a tote bag. It’s the only one here that can actually run a CPAP machine or keep a mini fridge cold all night.
Frequently Asked Questions
Which is better for camping: the Takki S81 or the Takki S811M?
The Takki S811M is much better for camping if you’re bringing any gear that needs real power. Its 222Wh capacity runs a 40W mini fridge for over 4.5 hours, while the S81’s 88.8Wh only manages about 2 hours. The S811M also has pure sine wave AC output at 250W, which means you can safely run sensitive electronics like CPAP machines or laptops without damage. I’d only recommend the S81 for ultralight backpacking where every ounce matters — it weighs just 2.29 pounds compared to the S811M’s 5.95 pounds.
Is the Powkey S99 worth buying over the Takki S81 if I only need to charge my laptop?
Yes, absolutely — the Powkey S99 is the better choice for laptop-only charging. It has 100W PD 3.0 fast charging through USB-C, which will charge most modern laptops at full speed, while the Takki S81’s USB ports max out at standard 5V/2.4A. The S99 also uses a LiFePO4 battery that lasts over 3000 charge cycles, so it’ll still be working years after the S81’s lithium-ion battery degrades. The trade-off is you get zero AC outlets with the Powkey, so you can’t plug in anything with a wall plug.
Can the Takki S81 power a CPAP machine?
No, I wouldn’t rely on the Takki S81 for a CPAP machine. Its AC outlet is limited to 80W running power with a 120W peak, and most CPAP machines with heated humidifiers draw 60-90W continuous. Even if it technically runs, you’d only get about an hour of runtime from the 88.8Wh battery before it cuts out. You need the Takki S811M instead, which has 222Wh capacity and 250W pure sine wave output — that can run a CPAP for over 4 hours without issue.
Which one is best for air travel?
The Powkey S99 is the only one I’d bring on a plane. It has a 96Wh capacity, which is under the 100Wh limit that most airlines enforce for carry-on batteries. The Takki S81 is close at 88.8Wh and technically under the limit too, but it’s bulkier at 5.7 x 4.13 x 3 inches compared to the S99’s compact cube design. The Takki S811M at 222Wh is way over the airline limit and won’t be allowed in your carry-on at all.
Is the Takki S811M worth the extra money over the Takki S81?
For most people, yes — the S811M gives you 2.5 times the capacity at 222Wh versus 88.8Wh, plus a much more useful 250W pure sine wave AC outlet compared to the S81’s 80W standard AC outlet. You can actually run real appliances like a mini fridge, CPAP machine, or a small TV with the S811M. The S81 is only worth saving money on if you’re absolutely certain you’ll never need more than phone and tablet charging with a small fan.
How long does each power station take to recharge?
The Takki S81 charges from 0% to 80% in about 2 hours using the included AC adapter, and a full charge takes roughly 4 to 5 hours. The Takki S811M charges via AC adapter but Takki doesn’t specify exact times — expect around 3 to 4 hours for a full charge based on its 222Wh capacity. The Powkey S99 is the fastest here, reaching 90% in just 1 hour when using a 100W USB-C charger, thanks to its PD 3.0 fast charging support.
My Final Verdict
The Takki S811M is my clear winner for anyone who needs real portable power — its 222Wh capacity and 250W pure sine wave AC outlet can actually run a CPAP machine or mini fridge, unlike the smaller S81. The Powkey S99 is a solid runner-up if you only charge laptops and want a LiFePO4 battery that lasts over 3000 cycles, but it has zero AC outlets. If you’re on a tight budget and just need emergency phone charging, the Takki S81 at 88.8Wh gets the job done in the smallest package.
If you’re stuck deciding between the S811M and the S99, ask yourself this: do you need to plug anything into a wall outlet? If yes, get the S811M. If all your devices charge via USB-C, get the S99 and enjoy that LiFePO4 longevity.
Winner: Takki S811M Portable Power Station
- Pure Sine Wave Outlet: With a battery capacity of 222Wh (60000mAh/3.7V...
- More AC/DC/USB Output Ports: This power station has 8 output ports...
- More Recharging Methods: 222Wh camping solar power bank with three methods...
This is the one I’d buy for myself — it has 222Wh of capacity, a 250W pure sine wave AC outlet that peaks at 450W, and it weighs just 5.95 pounds with a foldable handle. It’s the only unit here that can run a CPAP machine for over 4 hours or keep a mini fridge cold all weekend.
Runner-Up: Powkey S99 Laptop Power Station
- 【100W Fast Charging With Multiple Ports】 This laptop portable charger...
- 【Portable charger With 96Wh Capacity】 With an ultra-large capacity of...
- 【Charge 4 Devices Simultaneously】 Included USB-C cable,makes it easy to...
Perfect for travelers and remote workers who only charge USB-C devices — it has 96Wh capacity with 100W PD 3.0 fast charging, a LiFePO4 battery rated for over 3000 cycles, and it’s under the 100Wh airline carry-on limit.
Budget Pick: Takki S81 Portable Power Station
- FAST CHARGING: This portable power station can charge from 0% to 80% in...
- LARGER CAPACITY&SMALLER SIZE: With a battery capacity of 88.8Wh...
- 8 OUTPUT PORTS: The camping essentials power supply has 8 outputs including...
Best for ultralight backpackers or anyone who wants the absolute smallest emergency backup — it weighs only 2.29 pounds with 88.8Wh capacity and an 80W AC outlet. Just don’t expect it to run anything bigger than a laptop or small fan.
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