Head-to-head test
Anker SOLIX C300X vs Anker SOLIX C800
Real-world runtimes, scenario verdicts, and ownership costs compared — which wins for your use case.
Written by Wenny ZhengUpdated
Portable Power Tester, Station Arena Test Desk
Anker
SOLIX C300X
1,666Power Score · Device Hub
$299.99 list · direct from Anker
Anker
SOLIX C800
2,658Power Score · Appliance Class
$349.00 list · direct from Anker
Spec deltas
Two sizes from Anker's SOLIX C lineup: SOLIX C300X at 288Wh, SOLIX C800 at 768Wh. The $49 gap between them buys a fundamentally different tool. One you carry. One you place and leave. The SOLIX C800 has a slight edge, but the margin is close enough that your use case should break the tie.
The SOLIX C800's 768Wh keeps a fridge going for 4 hours. The SOLIX C300X's 288Wh manages 2 hours. The bigger unit rides out a full weekend outage. The smaller one needs a recharge by Saturday night. But if your actual use case is camping, tailgating, or keeping devices charged, the SOLIX C300X does the job at 9 lbs and $300 — no overkill, no regret.
Pick the SOLIX C800 if your primary use is cpap overnight. Go with the SOLIX C300X if you need the heavier-duty specs for demanding loads. Most buyers overlook this: the SOLIX C800 costs ~$0.15/kWh over its full lifespan, which adds up significantly over years of regular use. Keep scrolling for the full breakdown. The scenario verdicts below hold a few surprises.
Bench Notes
What each unit does well, where it falls short, and the trade-offs that matter.
Anker SOLIX C300X
At 300W, this unit is strictly for personal electronics (phones, laptops) and small CPAP machines. Do not expect to run kitchen appliances. At only 9 lbs, it is exceptionally portable. You can easily carry it one-handed to a campsite or tailgating party.
Strengths
- +Costs $49 less
- +Lighter by 14.8 lb
Trade-offs
- –Weaker inverter (-900W) limits appliance compatibility.
Anker SOLIX C800
The 1,200W inverter handles most daily devices like laptops, blenders, and TVs, but will struggle with heating elements that require over 1500W. At only 23.8 lbs, it is exceptionally portable. You can easily carry it one-handed to a campsite or tailgating party. A standout feature is the value proposition: at roughly $0.45 per watt-hour, it's one of the most cost-effective options on the market.
Strengths
- +Larger battery capacity
- +Higher AC output
- +Faster solar charging
Trade-offs
- –Significantly heavier (+14.8 lbs), making it harder to move.
Will It Power Your Gear?
Scenario math and per-appliance runtimes, modeled from the spec record.
Scenario verdicts
We ran the math on six real-world scenarios. Here's which unit survives your actual life.
SCN-01 · 2 nights · needs 2,100Wh
Weekend Camping
Two nights off-grid with essential comfort
Neither unit
Neither unit can fully handle this scenario (needs 2,100Wh). You'd need a higher-capacity station or to cut back on usage.
Battery budget usedlower = more headroom
LOAD Phone Charger 15W×6h · LED Lights 40W×8h · Box Fan 75W×14h · CPAP Machine 40W×16h
SCN-02 · 8 hours · needs 1,645Wh
8-Hour Blackout
Keep the essentials running through a night without power
Neither unit
Neither unit can fully handle this scenario (needs 1,645Wh). You'd need a higher-capacity station or to cut back on usage.
Battery budget usedlower = more headroom
LOAD Fridge 150W×8h · Router + Modem 20W×8h · LED Lights (4 bulbs) 40W×6h · Phone Charger 15W×3h
SCN-03 · 8 hours · needs 320Wh
CPAP Overnight
Sleep therapy without interruption — the #1 medical use case
SOLIX C800
The SOLIX C300X runs out of juice. It only has 245Wh usable, but this scenario needs 320Wh. The SOLIX C800 covers it and still has 22h of phone charging left over.
Battery budget usedlower = more headroom
LOAD CPAP Machine 40W×8h
SCN-04 · 8 hours · needs 910Wh
Remote Workday
Full work day off-grid without power anxiety
Neither unit
Neither unit can fully handle this scenario (needs 910Wh). You'd need a higher-capacity station or to cut back on usage.
Battery budget usedlower = more headroom
LOAD Laptop 60W×8h · External Monitor 30W×8h · Router + Modem 20W×8h · Phone Charger 15W×2h
SCN-05 · 4 hours · needs 670Wh
Tailgate Party
Game day power for the crew
Neither unit
Neither unit can fully handle this scenario (needs 670Wh). You'd need a higher-capacity station or to cut back on usage.
Battery budget usedlower = more headroom
LOAD Blender 400W×0.5h · LED TV (55") 80W×4h · Bluetooth Speaker 15W×4h · Phone Charger (×3) 45W×2h
SCN-06 · 24 hours · needs 4,685Wh
Van Life Daily
A full day of mobile living — the ultimate endurance test
Neither unit
Neither unit can fully handle this scenario (needs 4,685Wh). You'd need a higher-capacity station or to cut back on usage.
Battery budget usedlower = more headroom
LOAD Mini-Fridge 150W×24h · Laptop 60W×4h · Phone Charger 15W×3h · LED Lights 40W×5h · Fan 75W×8h
The Load Test
RUNTIME = (Wh × 0.85) ÷ LOAD
None of the six scenarios above exactly yours? Build it. Toggle what you'd plug in; both units are tested against the combined draw.
Essentials
Comfort & Convenience
High-Draw Appliances
Test duration
8h
Continuous draw
205W
Projected runtime
For this load: SOLIX C800 runs 3.2h vs 1.2h.
$349 list · direct from Anker
Modeled from the spec record — same math as the tables below. Methodology
Runtime by appliance
Real-world runtime estimates for common appliances, modeled at 85% inverter efficiency.¹
Essentials
The basics you need runningscale 0–43.5hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–8.7hHigh-Draw Appliances
These reveal the real limitsscale 0–0.7h¹ Runtime = (capacity × 0.85) ÷ appliance watts. Within each group, all bars share one time scale (the group's longest runtime), so lengths are comparable across appliances; identical runtimes collapse into a single blue/orange bar. Actual runtime varies with battery age, temperature, and simultaneous loads — see methodology.
Conclusion
July 10, 2026
Verdict: the SOLIX C800, on Power Score margin
These two units are closely matched on individual specs, but our Power Score analysis gives the SOLIX C800 the edge with a composite score of 2,658 vs 1,666.
Overall score margin: 1,666 vs 2,658 (−59.5%)
List prices as of July 10, 2026. The links below open Anker's current price.
$349.00 list · direct from Anker
or check the SOLIX C300X price$299.99 list
Written by Wenny Zheng, Portable Power Tester · Station Arena Test Desk · Updated July 10, 2026
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
Not rated for both units (minimum threshold unmet): Solar Generator.
Full specifications
| Specification | SOLIX C300X | SOLIX C800★ Our pick |
|---|---|---|
| Price | $299.99 Check latest price | $349.00 Check latest price |
| Capacity (Wh) | 288 | 768 |
| Output (W) | 300 | 1200 |
| Surge Peak | 600W | 1600W |
| AC Outlets | 3 | 5 |
| USB-C Charging Outputs | 140W | 100W, 30W |
| Solar Input (W) | 100 | 300 |
| Weight (lbs) | 9 | 23.8 |
| UPS | Yes (10ms) | Yes (<20ms) |
| Charging Cycles | 3000 | 3000 |
| Chemistry | LiFePO4 | LiFePO4 |
| Warranty (Years) | 5 | 5 |
| Battery Expansion Feasibility | No | No |
| App Control | Yes | Yes |
| $/Watt Hour | $1.04 | $.45 |
| Noise Level (db) | 25 | <45 |
| Solar Input Type | XT-60 (11-28V) | XT-60 |
| USB-A Ports | 1 | 2 |
| USB-C Ports | 3 | 2 |
| Cost per Whᵈ | $1.04/Wh | $0.45/Wh |
ᵈ Derived: price ÷ rated capacity.
Comparison ToolAdd more power stations, side by sideOpen Tool →How these numbers are produced
Numeric verification
Every figure on this page traces to our spec database or arithmetic on it — no estimated numbers.
Owner claims
Statements about owner experience are cited to published reviews.
Runtime model
Runtime = (rated capacity × 0.85 inverter efficiency) ÷ device wattage. Solar recharge estimates assume panels deliver 70% of rated output. Cold weather, battery age, and stacked loads reduce real-world results.
Power Score
Computed from 14 published spec dimensions, weighted per use-case bench. Higher is better; a unit must meet a bench's minimum threshold to be rated.
Test Notes & Caveats
Hidden gotchas and advantages we spotted that you won't find on the product page.
SOLIX C800: 45dB Under Load
45dB is about as loud as a running refrigerator. If you're running a CPAP or sleeping near this unit, the fan noise may be noticeable. Most people find anything above 45dB disruptive for sleep.
Surge Power: Inverter Quality Indicator
The SOLIX C300X has a 2× surge-to-continuous ratio vs the SOLIX C800's 1.3×. A higher ratio (≥2×) means the inverter handles motor startup surges better. That's critical for fridges, AC compressors, and power tools that briefly draw 2-3× their rated wattage. The SOLIX C800 may trip when starting these appliances even though its continuous wattage looks sufficient.
UPS Speed: line-interactive (<10ms) vs standby (<20ms)
The SOLIX C300X switches to battery in 10ms (line-interactive (<10ms)), while the SOLIX C800 takes 20ms (standby (<20ms)). Safe for desktop PCs, routers, and CPAP machines. NAS drives are protected. This matters if you're using it as a home UPS for always-on equipment.
Warranty Value Comparison
The SOLIX C300X gives you 16.7 years of warranty per $1,000 spent, vs the SOLIX C800's 14.3 years. That's 1.2× more coverage per dollar. An underrated factor if you're keeping this unit for years.
Full record above — the Test Desk pick is the SOLIX C800.
Check SOLIX C800 price →or check the SOLIX C300X priceOwnership Analysis
What happens after you buy — true cost of ownership, brand trust, and growth potential.
Lifetime value
Service lifeyears at one full cycle per day
Lifetime energy delivered
Cost per delivered kWh
│ warranty ends · Reaching the cycle rating means ~80% capacity remains — degraded, not dead.
| Metric | SOLIX C300X | SOLIX C800 |
|---|---|---|
| Purchase price | $299.99 | $349.00 |
| Lifetime energy delivery | 864 kWh | 2,304 kWh |
| Cost per lifetime kWh | $0.35 | $0.15 |
| Cost per warranty year | $60/yr | $70/yr |
| Battery lifespan | 8.2yr daily · 28.8yr weekends · 57.7yr weekly | 8.2yr daily · 28.8yr weekends · 57.7yr weekly |
Analyst note
The SOLIX C300X is cheaper to buy, but the SOLIX C800 is cheaper to own. At $0.15/kWh over its lifetime vs $0.35/kWh, the SOLIX C800's higher cycle life and capacity make each dollar go further over the years.
Delivers each lifetime kWh for $0.20 less — check the SOLIX C800 price →
Growth path
SOLIX C300X
FIXED CAPACITYFixed at 288Wh, with no expansion — so size it for your needs up front rather than planning to add capacity later.
Accepts up to 100W of solar. Limited to a single portable panel.
Adequate ports for most setups, but heavy users may want a power strip.
SOLIX C800
FIXED CAPACITYFixed at 768Wh, with no expansion — so size it for your needs up front rather than planning to add capacity later.
Accepts up to 300W of solar. Limited to a single portable panel.
Adequate ports for most setups, but heavy users may want a power strip.
Realistic full solar rechargeat 70% of rated panel output — see methodology
Analyst note
Neither expands, and that's no knock on either — each is a complete unit at a fixed size. Buy the capacity that covers your needs now (the SOLIX C800 gives you the larger ceiling); you can't add to either later.
The Bottom Line
The full picture comes down to this. The SOLIX C800 edges ahead on our overall analysis, but the margin is narrow enough that your specific use case should drive the decision. Review the scenario verdicts above — if the SOLIX C300X wins in the scenarios that match your life, it's the right choice regardless of aggregate scores.
If neither the SOLIX C300X nor the SOLIX C800 feels like the right fit, your power needs probably sit outside what these two target. If you're planning whole-home backup or running power-hungry appliances (electric heaters, window AC), you'll want a larger system in the 3,000–5,000Wh range with expansion battery support. Prices on portable power stations fluctuate frequently. Both Anker discount regularly, so check the current price before committing. Prime Day and Black Friday pricing typically drops 20-30%.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
Can I actually carry the SOLIX C800, or is the SOLIX C300X the only portable option?
The SOLIX C300X at 9 lbs is genuinely grab-and-go. Toss it in a backpack, carry it one-handed to a picnic, take it on a boat. The SOLIX C800 at 23.8 lbs is a different story. It's like carrying a large suitcase full of books. If you're setting up and breaking down camp frequently, this weight difference will exhaust you by day two.
Bottom line: should I buy the SOLIX C300X or the SOLIX C800?
We'd pay the premium for the SOLIX C800. Yes, it costs more. The capability jump is real: you're stepping into a tier that handles appliances the base model can't start. The SOLIX C300X is still solid if budget is the priority, but the SOLIX C800 will leave you less likely to wish you'd "gone bigger" six months from now. That regret costs more than the price difference.
Where to buy
Anker SOLIX C300X
$299.99
$299.99 list · direct from Anker
Anker SOLIX C800Pick
$349.00
$349.00 list · direct from Anker
Prices may vary by retailer and are subject to change.