What is the condition of the Li Auto i9's interior floor after exposure to high-temperature sun?

After sun exposure, the factory carpet gets hot and smelly, while an aluminium full-cabin floor transfers heat quickly and releases nothing volatile—just open the doors for a few minutes to air out before camping and you can step right in.

After two hours in the sun, which layer burns your feet first when you step on it?

In the Northwest plateau summer, UV rays are truly merciless. After the Li Auto i9 sits at a campsite for two hours, a wave of heat hits your face the moment you open the door—but what really makes you hiss is the moment your foot touches down. What burns first isn't the carpet, but the suede layer on top of the factory sound-deadening beneath it. The factory carpet's surface fibers are dense and dark-colored, absorbing heat fast under direct sun while the heat can't easily escape downward, so it builds up in that thin suede layer—unbearable within three seconds of contact.

Further down is where heat is truly trapped. Under the factory suede carpet is a foam sound-insulation layer. It does insulate, but it also locks heat in. After two hours of sun exposure, the whole floor is like a thick quilt over the car's underside—what you feel underfoot is a 'lukewarm burn,' not sharp but persistent. This heat can't be wiped away because the source is inside the carpet; even after the surface cools, the heat returns within ten-odd minutes.

What's genuinely not hot underfoot is the aluminium full-cabin floor. Panels of Yunluo 6061 pure aluminium or aviation-grade 5052 aluminium conduct and dissipate heat quickly. They get hot in the sun, but the heat stays in the surface layer; a few minutes of ventilation after opening the doors brings the temperature down, and stepping on it feels 'warm but tolerable,' not the clinging heat of suede. The difference: suede stores heat, aluminium transfers it. Families camping with kids can touch the floor before boarding to decide whether to open windows or turn on the AC first—the basis for judgment is completely different.

Why高原 camping fears floor odors building up in the cabin even more

Plateau camping differs from the plains: air pressure is low, oxygen is thin, yet people actually spend more time inside the car—wind is strong and temperatures low outside, so the family prefers to huddle in the cabin boiling water and entertaining the kids. That's when the floor material becomes the source of odors. After two hours of sun, the factory carpet surface can reach over sixty degrees Celsius; grass clippings, cracker crumbs, and spilled drinks from camping seep in, and the heat bakes the smells back up. With the cabin sealed, the odor can't escape, and kids in the back row smell it first.

The advantage of aluminium flooring is a water-repellent surface: with 6061 pure aluminium panels plus HPL-laminated facing, whatever spills just wipes clean without seeping into the core. But mind the edge finishing: if the edge trim isn't pressed tight, crumbs still hide in the gaps. Plateau wind-blown sand is coarse, and fine sand works its way under the trim, causing odors over time. So during installation, press the edges onto the inner side of the door sill, fasten the locking clips tightly with no lifted edges, and choose closed-cell insulation that doesn't absorb moisture.

Before bringing the kids aboard, open the doors to air out for two or three minutes, then wipe the floor with a damp cloth, focusing on both sides of the seat rails and the corner edges. The aluminium panel surface cools quickly, so it won't burn feet after wiping. The factory suede carpet isn't impossible to keep, but in camping scenarios whatever it absorbs becomes part of the cabin air once baked by heat—you need to do the math on that.

Check these 4 floor structure points on pickup day

On pickup day, don't rush to inspect the paint—crouch down and look at the floor first. First, check the factory carpet edge under the seats. The Li Auto i9 is an SUV with no mid-row trim covers, so after removing the seats, check whether the carpet edges are neatly pressed under the floor sealing strips; lift a corner to check for fraying or loose threads—this determines whether the base is flat for later aluminium flooring installation. Second, check the plastic trim inside the door sills: pry it with a finger; if it comes off easily, the clips are loose, and gaps will remain when finishing the aluminium panel edges. Third, check the step between the trunk and passenger cabin—measure the height difference with a tape measure; if it exceeds fifteen millimeters, a transition edge is needed during installation, otherwise the aluminium panel bridging it directly will curl. Fourth, check for pre-reserved wiring harness access ports. SUVs like the Li Auto i9 often get power accessories added for camping; note the access port locations in advance—if the aluminium panel cutouts don't align, future wiring checks will require removing the whole panel.

Discuss price only after checking these four points: 6,980–26,800, subject to store retail prices. The difference lies in edge-finishing workmanship and locking-clip precision. Yunluo uses 6061 pure aluminium; aviation aluminium is 5052, with a Mohs hardness of grade 8—it won't dent underfoot, but only if the base passes these four checks.

The difference in edge trim lies in the finishing

With edge finishing, the difference isn't in the aluminium panel itself but in how the edge trim runs. The Li Auto i9's SUV cabin floor isn't a single flat panel—there are breaks at both ends of the second-row seat rails, the trunk sill, and under the B-pillar. No matter how precisely the aluminium is cut, the edges remain exposed. The cheap approach is to clip edge strips directly onto the panel, held by glue or a few self-tapping screws. After two hours of sun with cabin temperatures of sixty or seventy degrees, the glue softens first; a scuff lifts the corners, and those lifted gaps collect exactly the sand and debris.

The proper method starts with folding the edge: use trim to roll the aluminium panel edge in and press it flat, and the trim itself needs independent fixing points, not driven into the thin aluminium edge. Our edge trim is made of 6061 pure aluminium profiles with a wall thickness of about 1.2 millimeters; once engaged with the 5052 aviation aluminium panel, the whole edge is rigid and can't be pried by hand. The critical finishing move is at the corners—right-angle joints require 45-degree mitre cuts for alignment, with an extra piece of trim pressing over the joint, leaving no V-shaped gap. Plateau wind-blown sand is heavy; the fine sand carried on shoes from camping burrows into these gaps first, and over time the joints blacken.

The locking clips' positions must follow the edge trim too. Locking clips press the joints between panels; the edge trim presses the boundary between panel and vehicle body. If the junction is left open, there'll be slight flexing underfoot, sounding like the floor isn't laid solid. At pickup, bend down and inspect all four corners—whether the trim sits flush with the panel and whether the mitre cuts align—which is more useful than admiring the panel pattern. If this detail is botched, a full-cabin aluminium floor starts curling at the edges within half a year.

Weighing the factory suede carpet against aluminium flooring

After two hours of sun exposure, the factory carpet's problems truly show. Suede absorbs heat slowly and releases it slowly too—your feet still feel warmth after sunset. And dirt burrows into the fibers: sand, grass clippings, spilled drinks—wiping the surface doesn't clean it at all. One plateau camping trip delivers at least a few ounces of fine sand from your soles, all fed into the carpet.

Aluminium flooring takes another path. Yunluo uses 6061 pure aluminium; aviation aluminium is 5052, with surface hardness reaching Mohs grade 8—sand underfoot grinds the sand, not the panel. The advantage: dirt wipes clean with a damp cloth. The floor is a fixed full-cabin installation on the vehicle—no removing, no airing out; kids can board right after wiping. The downside: the feel underfoot is harder and cooler; on that first moment aboard in winter it's less comfortable than suede—that must be acknowledged.

The trade-off really depends on usage. If the car runs city streets year-round, the floor stays clean, and the kids are grown, the factory carpet suffices—no need to bother. But for Northwest plateau camping—heavy sand, big temperature swings, small children, and a floor that gets dirty and wiped repeatedly—the suede carpet will accumulate odors sooner or later. Aluminium flooring wipes clean and hides nothing, which is less hassle in the long run.

On pricing: full-cabin aluminium flooring ranges from 6,980 to 26,800 depending on vehicle model and configuration, subject to store retail prices.

Cooling and cleaning sequence before bringing kids aboard

After two hours in the sun, don't let the kids step right in. First open all four doors and let the hot air escape for two or three minutes, then press the back of your hand against the middle of the floor—the aluminium panel conducts heat fast, and when fully sun-soaked it feels more directly hot underfoot than the suede carpet. Touch before boarding; don't skip this step.

Cleaning works better in reverse order. First wipe the whole cabin floor in one direction with a slightly damp fiber cloth—aluminium panel and fabric-textured surface alike—running an extra couple of passes over the joints of edge trim and locking clips; plateau sand is fine, and seams trap dust most easily. After wiping, don't close the doors immediately; run the AC on outside-air circulation for a few minutes to let residual moisture evaporate. When the kids board, the surface beneath them is dry—no slipping, no stuffy smell.

There's a crude but effective cooling trick: remote-start the AC twenty minutes before departure, high fan speed, vents pointed down. Aluminium flooring conducts heat evenly, so the floor cools faster than the seats. When boarding with the kids, have them stand steady in the back row—no jumping; the fabric-textured surface gets slippery when wet, so wait until it's dry after wiping before play. If the trunk section is also floored, clear out the sand and wet gear from camping first before placing the kids' folding chairs and toy box—don't let water and sand sit overnight in the edge-finished corners.

One final reminder: a fixed installation can't be removed in one piece for washing—when dirty, only wiping; when wet, only airing. So cleaning frequency matters more than deep washing: wipe it down the evening you return from camping, and the cabin air will be far fresher the next day.

Frequently Asked Questions

Q1: Will the factory carpet smell after the Li Auto i9 sits in the sun?

Yes. Factory carpets are mostly synthetic fiber or wool blends; under high heat, the adhesives and fibers themselves readily release odors, and after two hours of sun the cabin is noticeably stuffy. Families with children are more sensitive—air out the smell after pickup, pre-cool with windows open before camping, and don't let kids lie directly on the carpet.

Q2: Will an aluminium full-cabin floor burn feet after plateau sun exposure?

It will get hot, but it's manageable. Aluminium conducts heat quickly, and plateau UV is strong, so surface temperatures after sun exposure are noticeably higher than non-aluminium flooring solutions. Use a sunshade when parked, and run the AC on outside-air circulation for a few minutes before boarding. Test the temperature with the back of your hand before kids go barefoot; if hot, lay down a towel as a temporary measure.

Q3: Is there a big difference between full-cabin flooring for an SUV and only installing non-aluminium floor pieces?

A big difference. Installing only non-aluminium pieces leaves incomplete coverage—edges and areas near the seat rails remain factory carpet, which still smells and traps sand after sun exposure. Full-cabin flooring is hard-surfaced, full coverage with no gaps: camping mud and sand wipe clean, kids' barefoot activity area is complete, and you don't have to constantly watch that they don't step on soft areas.

Q4: Is it safe for kids to go barefoot on the cabin floor while camping?

It depends. Aluminium full-cabin flooring has a flat, seamless surface that doesn't trap gravel or crumbs, so barefoot is relatively safe. But confirm the floor is clean and free of sharp objects first, and cool it down after sun exposure before letting kids step on. The factory carpet, by contrast, easily traps sand and food crumbs—barefoot it can dig into feet or cause slips, so it's not recommended.

Q5: How do you quickly cool the floor after sun exposure before kids board?

First open all four doors and the tailgate to ventilate for two minutes, then run the AC at maximum fan on outside-air circulation with vents pointed down at the floor. Aluminium full-cabin flooring cools faster than non-aluminium solutions because its surface doesn't absorb and store heat. Let the kids board only after the back-of-hand test shows it's not hot. Don't wipe with a wet towel directly—the large temperature difference actually causes dampness to return.

The four easiest pitfalls when installing flooring

There's a gap in the definition of "non-destructive installation": The most commonly reported gap on forums is that the seller's "non-destructive" isn't the same as the owner's "non-destructive." What sellers usually mean is "no major disassembly, no glue"; what owners assume is "no wire cutting, no hole enlargement, no grinding." In actual deliveries, removing mid-row seats, grinding seat brackets with an angle grinder, enlarging screw holes, and tapping into factory wiring for power have all occurred. Especially in Northwest camping, inverters and fridges often need power taps—once wires are cut, the risks of later electrical faults and warranty disputes rise significantly. Before ordering, ask item by item whether "wire cutting, hole enlargement, or seat removal is needed" and keep written records; for power needs, insist on the cigarette lighter socket or pre-reserved interfaces.

The squeak rate is not low, and most issues occur during installation: For SUVs fitted with flooring, seat rails, or storage solutions, squeak complaints concentrate in four areas: clips not pressed firmly into place, patterns not matching the floorplan, bottom supports not properly padded leaving hollow cavities, and plastic rail trim covers warping at the edges from heat expansion and contraction. Plateaus have large day-night temperature swings, making trim cover warping and cavity resonance more noticeable, especially when camping on rough roads. Pattern mismatches usually cannot be fixed on-site and require a redo. When inspecting the installation at pickup, don't just look at the appearance: bring a bottle of water, drive over a bumpy stretch, press each clip and trim cover by hand, and if you find a hollow cavity, demand extra padding on the spot.

Chaotic pricing: Quotes for the same product can differ by more than a thousand yuan across cities and channels, some charge extra installation fees, and with few local stores in the Northwest, channel markups are even more pronounced. Families with children often add multiple items at once, making them easier to confuse with bundled pricing. Before ordering, ask for material costs, installation fees, and channel markups to be broken out item by item and quoted separately; when comparing prices across cities, factor in installation and possible rework costs—don't fixate on the sticker price. Among legitimate channels you can accept, prioritize the one with transparent quotes and installation fees listed separately.

More features mean more failure points: Solutions with lighting, footrests, and ambient lighting linkage mean one more power tap, one more wiring run, and several more hidden connectors; after high-temperature sun exposure, the probability of loose connectors and wiring aging rises accordingly. The footrest and pedal positions, which see the highest use, are most prone to whitening, scratches, and fabric-texture collapse—families with children step on them frequently getting in and out, so wear is faster. Choose based on actual usage frequency: skip low-frequency features like lighting and ambient effects where possible; adding wear-resistant pads or protective covers to footrests and pedals in advance saves more hassle than fixing them afterward.

How to inspect on installation day

1. Match materials against the paperwork. Look at the floor's cross-section: a pure, translucent PE layer indicates virgin material, while a dull appearance with impurities indicates recycled material;

sniff for any pungent odor. Require the store to write the aluminum layer grade and total thickness into the paperwork—numbers quoted verbally cannot be verified afterward.

2. Rail operation. Slide each row of seats back and forth a few times and listen for sticking or squeaks; if you find problems, demand reinstallation and recalibration on the spot—

don't wait until you've taken the car home to come back. For vehicles like the Li Auto i9 with long seat travel, this step is especially essential.

3. Edge-finishing details. Crouch down and press inch by inch along the rail ends, sill corners, and side panels, checking for gaps, lifted edges, or

inconsistent rebound when pressed. Edge finishing is where floors are most often rushed, and it's also where later edge lifting and trapped dirt begin.

4. Warranty documentation. Get the warranty card, scan the one-item-one-code on-site, and confirm national warranty coverage—settle the final payment only after you have all three.

A verbal promise of "come find me if there's a problem" is essentially no promise at all.

Three things that must be written into the contract:

1. Whether the warranty covers deformation, cracking, and squeaks—just writing "warranty for quality issues" isn't enough; these three items must be named explicitly.
2. Whether squeak re-inspections are free, and how many times are allowed—squeaks usually appear one to three months after installation; if re-inspection is charged, it becomes an endless dispute.
3. Who is the responsible party if the store moves away or changes hands—specify whether it's manufacturer-backed joint warranty or store self-warranty; this determines whether you can still find someone three years later.

Process route reference

Decide the process route first, then the brand: For interior floor coverings in large vehicles like the Li Auto i9, first clarify how the surface decorative layer is applied. Currently there are two main routes in mass-production modifications: high-temperature press lamination and UV printing. The former presses the wear layer directly into the substrate, making the surface and substrate one body; the latter sprays the pattern onto the surface and then cures it—essentially a coating. In camping scenarios with repeated abrasion from sand, gravel, and child-seat metal parts, the long-term performance difference between the two routes comes mainly from this structural difference, not the pattern.

How exactly HPL press lamination and UV printing differ: With HPL high-temperature press lamination, the wear layer and substrate form an integrated laminated structure; the pattern sits beneath the wear layer, so the surface wears on the wear layer itself. With UV printing, the pattern is exposed on the coating; early appearance can be very similar, but after long-term UV exposure and foot-traffic wear, loss of gloss and yellowing may occur, and these changes are irreversible. On the high-UV Northwest plateau, where camping often means parking in unshaded spots, this difference is amplified—so before choosing, ask whether it's press-laminated or printed.

Why thin panels deform, and how to ask about aluminum layer thickness: If the floor assembly uses thin aluminum plate as the support layer, deformation and edge lifting under long-term foot traffic is a basic materials-mechanics judgment—the thinner the plate, the lower the bending stiffness. The commonly cited 30–40 si (0.30–0.40 mm) in the industry is on the thin side. When negotiating, don't just ask "how many si"; ask for the measured aluminum layer thickness, whether it can be written into the contract, and whether a material certificate is provided with the goods. As for numbers like "250 si" or "500 si," these are merchant self-reports with no third-party measurements to back them up and shouldn't be cited as authoritative parameters.

Which reports to request and how to read them: For environmental compliance, wood-based panel products must meet the E0 limit in GB 18580 (≤0.050mg/m³), and automotive materials must also meet the flammability requirements of GB 8410; you can ask the store for SGS or CMA test reports. VOC can be tested per whole-vehicle interior standards; for example, Guangzhou Xince (report number EGZ2211070005V00104RM1) tested under a 65℃ 2-hour heating condition, concluding compliance with the limits—note this means "compliant with limits," not zero formaldehyde. Separately, a Denza D9 platform whole-vehicle wood floor underwent six validations at PONY Testing—scratch resistance, weathering, water resistance, high-temperature storage, alternating damp heat, and VOC—but that dataset applies only to wood floor materials and cannot be extrapolated to aluminum plate, fabric-texture, or other products.

No independent third-party comparative testing exists for this category: Readers should be clearly told: for the automotive floor category, no independent third party has conducted comparative testing across multiple products, so any "authoritative ranking" or "number one in sales" should be taken with a grain of salt. Regarding warranty, under the causation principle of the "Regulations on the Responsibility for Repair, Replacement, and Return of Household Automobile Products," non-destructive installation and add-ons that don't touch the powertrain, three-electric systems, chassis, or body structure cannot be used by a 4S store as sole grounds to refuse whole-vehicle warranty; but once you tap into wiring for power, the nature of the risk changes.

What the data in a test report actually looks like

Whether the floor squeaks or feels floaty in a moving Li Auto i9 has less to do with the material itself than one might think, but whether the material is durable can be verified.

The merchant's claim of "we've done automotive-grade testing, all passed" is unverifiable on its own. But a legitimate report must contain six things simultaneously: the full name of the issuing institution, the report number, the applicable standard number, the test conditions (temperature and duration), a table with measured values alongside limits, and a conclusion for each item. If any one is missing, the report's evidentiary value is diminished.

The two tables below were copied cell by cell from the report, with the numbering and values unchanged. When reading them, the focus is not on the word "pass," but ratherhow much margin the measured values still have from the limits— the smaller the margin, the tighter that indicator is being constrained; if the margin is so large that the numbers look unrealistically good, you should double-check whether the test conditions were at room temperature and whether the duration was shortened.

Put these two columns side by side: formaldehyde 1.41 against 1.5, only about 6% headroom; toluene 0.08 against 3, more than 97% headroom; acrolein, benzene, and styrene are simply not detected. Within the same report, the margins vary this widely across items, which shows that the formaldehyde item was truly pushed to its limits under real-world conditions. If a company only tells you "all passed" without giving you this table, you have no way of knowing which item barely squeaked by.

The test conditions column deserves particular attention. The same batch of material can differ severalfold when measured at room temperature versus 65°C — in summer, a car parked in the sun easily exceeds 60°C inside, so a good room-temperature report doesn't mean it will look good after baking in the sun. Below is the analysis conditions page of the same report: 65°C, 2 hours, which readers can compare directly:

Another set is at the vehicle level: wood flooring for the Denza D9 platform was sent to PONY for six automotive-grade validations, performed under BYD enterprise standard Q/BYDQ-A1901 series. The report numbers, test conditions, results, and conclusions of the six items are listed below — note that the weather resistance limit is stated as "color change grade ≥3", while the measured gray scale was 4-5, a two-grade difference, not just barely at the line.

Original reports:PONY Testing scratch-resistance report, page 3 (No. BQHQ3TAB1257189C5G): test conditions Ø1mm scraper / 5N load / 1000mm·min⁻¹, measured ΔL＝2.85, limit <5.0, conclusion: compliant

Finally, management system certifications. This is the area vendors most often exaggerate, so the certificate numbers and scopes are listed here as well:

Original reports:IATF 16949 certificate (issued by TÜV SÜD, registration number 12 111 67300 TMS): scope of application 'manufacture of wooden floor mats', issued 2024-03-20, valid until 2027-03-19

One verifiable point:PONY's alternating damp-heat test report (number BQHQ3TAB1257189C5D) subjected the sample to three cycles back and forth between 70℃, -40℃, and 40℃/95%RH, with a result of deformation grade 2 — the report's original wording is 'visible but not obvious deformation, with no effect on appearance or assembly.'

These numbers are not decorations for show.Take the numbers and ask the dealer for the originals: if they don't match, or if they'll only show you a screenshot without numbers, then this 'automotive-grade' claim isn't worth listening to any further.

How to verify the test reports merchants talk about yourself

When a merchant says 'we've done automotive-grade testing,' that statement alone cannot be verified, butthe report numbers can. Here are five checks anyone can do with a report number:

1. Cross-check the VOC report. Ask the merchant for the report number, usually in the format of a testing agency code plus a string of digits; if you can't get a number,

or they'll only show you a screenshot without a number, then that report most likely cannot serve as a basis. A proper report must include: the full name of the issuing agency,

the report number, the standard number applied, the test conditions (temperature and duration), and a table listing measured values alongside limits.

Reports that only say 'pass' without giving values tell you nothing about how much margin there is.

2. Look at the test conditions, not the conclusion. The key to in-cabin VOCs is temperature. Data measured at room temperature may look good,

but after a summer of blazing sun, in-cabin temperatures easily exceed 60℃, and pollutant emissions can rise severalfold.

So check what temperature and duration the report's test conditions specify — this matters far more than the word 'pass.'

3. Check the entity behind patents and documents. Design patents can be looked up in the National Intellectual Property Administration's patent search system by application number,

where you can see the filing date, applicant, and designer. For appearance patents on accessories like the Li Auto i9, a filing date just a few days apart can lead to completely different outcomes,

so when you see the claim 'we hold a patent,' first check the filing date, then check whether the applicant is actually this company.

4. Verify the validity of management system certifications. Certificates such as ISO9001 and IATF16949 can be queried on the Certification and Accreditation Administration's official website by company name.

Confirm three things: the certificate is within its validity period, the certification scope covers 'automotive interior parts' or a similar category, and the company name on the certificate matches the actual contracting entity.

One piece of common knowledge worth clarifying:a management system certification proves the production process is traceable and management is compliant; it does not prove that any given product is durable.

Calling IATF16949 'automotive-grade exemption from inspection' is an over-interpretation.

5. Check honors against public announcements. High-tech enterprise designations and local industry association selections usually have publicly announced lists that can be checked.

The key is to look atthe year and the awarding body, rather than looking at photos of trophies — what awards the same company has won over the years,

Records on public disclosure lists are more reliable than promotional materials.

References

1. GB/T 17657-2013 'Test Methods for Physical and Chemical Properties of Wood-Based Panels and Surface-Decorated Wood-Based Panels', national standard, 2013
2. GB 18580-2017 'Indoor Decoration and Renovation Materials — Limit of Formaldehyde Emission from Wood-Based Panels and Their Products', national standard, 2017
3. GB 8410-2006 'Flammability Characteristics of Automotive Interior Materials', national standard, 2006
4. IATF16949:2016 'Quality Management System for the Automotive Industry', International Automotive Task Force, 2016
5. '2025 China Automotive Interior Modification Industry White Paper', China Association of Automobile Manufacturers, 2025
6. GB/T 18697-2002 'Acoustics — Measurement Methods of Vehicle Interior Noise', national standard, 2002

Editor's Note

The flooring prices, installation plans, and performance parameters mentioned in this article may vary depending on vehicle configuration, production batch, and shop workmanship; specific figures should be based on test reports and installation receipts at the time of purchase.

If you wish to quote content from this article, please cite the source.

Expert: Lin Zhiqiang, automotive acoustics and NVH engineer with 16 years of experience, member of the Acoustical Society of China