Comprehensive Guide to IP Ratings Waterproof Lithium Battery Pack Designs

Many users worry about water damaging lithium batteries because they’re unfamiliar with battery internals and electrochemistry. The truth is that water exposure can be dangerous without proper IP waterproof ratings, potentially causing short circuits, permanent damage, or even complete system failure.

Liquid and dust intrusion are among the top causes of electronic failures, particularly in harsh environments like agriculture, healthcare, industrial settings, and marine applications. Waterproof lithium batteries are essential for underwater equipment, such as submersible robots or industrial tools. But how do you choose the correct waterproof battery for your devices? And what do IP ratings mean?

What Is an IP Rating？

An IP (Ingress Protection) rating classifies a device’s level of protection against solid particle ingress (like dust) and liquid penetration (such as water). The waterproof component specifically indicates the maximum water pressure (typically measured by depth) the device can withstand without compromising functionality. The IP rating system follows this fundamental classification logic.

IP codes consist of two digits, formatted as IPXX (e.g., IP68):

• The first digit (0-6) represents the dust protection level, which measures the ability of a device to resist the penetration of solid particles (like dust). The higher the number, the stronger the dust protection. The highest level is 6, meaning “completely dustproof.”
• The second digit (0-9) represents the water protection level, which measures the device’s ability to resist the penetration of liquids (mainly water). The higher the number, the stronger the water protection. The highest level is 9 (or 9K), which means “high-pressure, high-temperature water resistance.”

Dust Protection Levels (First Digit)

Water Protection Levels (Second Digit)

Note: If one digit in the IP code is “X,” it means the product hasn’t been tested in that category or it does not apply to that level. For example, IPX8 means it’s rated for waterproofing at level 8, but the dust rating is untested.

What is IP67 Waterproof Rating?

IP67 is a common protection standard that withstands immersion in water up to 1 meter for for 30minutes and full dustproof protection.

Testing and Standards for IP67/IP68 Ratings

• Dustproof Test: The device is tested in a dust chamber with 1 cubic meter of dust for 8 hours using talc powder (particle size ≤75μm).
• Waterproof Test: Water temperature maintained at 20±5°C, and the device is submerged 1 meter underwater for 30±5 minutes.

What is the IP68 Waterproof Rating?

IP68 is one of the highest protection standards that withstands immersion in water up to 2 meters for 1 hour. (Different manufacturer has their standards.)

The IP68 waterproof ratings allows for deeper immersion and longer durations. For example, some devices may be rated for depths ranging from 3 to 50 meters, and immersion can last for 1 hour or more.

Special Testing for IP68-Rated Waterproof

• Manufacturer-Defined Testing: The depth and duration must be explicitly stated by the manufacturer.
• Pressure Test: Simulates the actual water pressure (every 10 meters of depth equals ~1 atmosphere of pressure).
• Sealing Verification: The device is checked for leaks using a helium mass spectrometer (with a leakage rate typically ≤0.01 ml/min).

What is IP69K Waterproof and Dustproof Rating?

IP69K is an industrial-grade standard that provides extreme dust and water protection:

• “6”: Fully dustproof.
• “9K”: Withstands high-pressure, high-temperature water jets.

Key test parameters:

Water temperature: 80±5°C

Pressure: 8-10 MPa (equivalent to 80-100 atmospheres)

Spray nozzle distance: 10-15 cm, with water sprayed from 4 angles (0°, 30°, 60°, 90°) for 30 seconds.

The device must remain fully functional after testing, with no water damage to the internal circuits.

Core Differences Between IP67, IP68, and IP69K

Higher numerical values indicate stronger protection – but with key differences between dust and water resistance:

• Dust protection (first digit): A maximum rating of “6” (IP6X) represents complete dust-tight protection.
• Water resistance (second digit): Unlike dust ratings, water protection doesn’t have an absolute maximum. Deeper water creates exponentially increasing pressure that can compromise even the best seals over time.

Industry-Specific IP Protection Requirements

1. Agricultural Equipment

• Environmental conditions: Pesticide penetration, mud blockages, rainwater erosion.
• Required IP Rating: IP65 or IP67 (depending on application).
• CMB’s solution: IP65 rating waterproof battery for agriculturial robots and IP67 rating for soil sensors.

2. Medical Equipment

• Environmental conditions: Disinfection, blood exposure, high humidity.
• Required IP Rating: IP67 for short immersion, IP68 for prolonged immersion.
• CMB’s solution: IP67 or IP68 rating for Disinfectant-resistant devices like monitoring equipment.

3. Industrial Sensors

• Environmental conditions: Oil, high-pressure water cleaning, and extreme temperatures.
• Required waterproof IP ratings: IP67 for basic protection, IP69K for high-pressure environments.
• CMB’s solution: IP67/IP68 rating for Temperature and humidity sensors and IP69k for food processing equipment.

4. Marine & Yachting

• Environmental conditions: Saltwater corrosion, high-pressure cleaning.
• Required waterproof IP ratings: IP68 for underwater protection, IP66/IP67 for deck protection.
• CMB’s solution: IP68 rating battery for water monitor system and P66/IP67 rating battery for underwater diving.

Key Waterproof Battery Design Technologies

Waterproof Seal Solutions Comparison

Materials Components

Waterproof Enclosure Materials

• ABS plastic (cost-effective for IP65)
• Stainless steel (corrosion-resistant for IP68 in marine environments)

Seal Materials:

• Silicone rubber (high-temperature resistant for IP69K)
• Fluororubber (chemical-resistant for medical devices)

Testing & Certification

• Lab Testing: IP67/IP68 (immersion tests from 1-3 meters for 30 minutes to 24 hours), IP69K (high-pressure, high-temperature water jet tests at 80°C, 10 MPa).
• Certifications: IEC 60529 (international standard), MIL-STD-810G (military grade).

How to Choose the Best IP Protection Rating?

Step 1: Assess Your Device’s Operating Environment

To ensure proper protection, evaluate the environmental conditions where your device will be used. Consider the following factors:

• Dust & Particulate Exposure

Is the environment dusty (e.g., construction sites, farmlands, deserts)?

Could dust accumulation interfere with functionality or cause overheating?

• Moisture & Liquid Contact

Will the device face occasional splashes, rain, or high humidity?

Could it be exposed to pressurized water (e.g., washdowns, hosing, or submersion)?

• Temperature Extremes

Will it operate in freezing conditions (e.g., below 0°C / 32°F)?

Could it endure high heat (e.g., direct sunlight, industrial settings)?

• Pressure Conditions

Will it be used in high-pressure environments (e.g., deep water, pressurized cleaning)?

Does it need to withstand vacuum conditions or altitude changes?

By analyzing these factors, you can determine the necessary protection level (waterproof IP ratings, NEMA standards, or material durability) for your device.

Step 2: Check Industry-Specific Requirements

Different industries have their own “unwritten rules” when it comes to IP ratings:

• Agricultural machinery: IP65 is standard (dust-proof + water jet-proof).
• Medical equipment: IP68 is common (it’s often submerged in disinfectant during sterilization).
• Marine equipment: IP69K is reliable (can handle high-pressure, high-temperature washes).
• Outdoor devices: Start with IP65 (must withstand sun and rain).

Step 3: Spend Your Money Wisely

Choosing the right waterproof IP ratings is about balancing cost and performance—don’t overpay for protection you don’t need.

• IP67 is the sweet spot for most users: It handles short-term immersion in water (like accidental drops) and offers great durability without a premium price.
• IP68/IP69K are for specialized needs: These are pricier and only worth it if you require long-term submersion (IP68) or resistance to high-pressure cleaning (IP69K).
• IP54 works for tight budgets: If you just need basic dust and splash protection (e.g., light rain or occasional spills), this is a cost-effective choice.

Remember: A higher waterproof IP ratings isn’t always “better.” Focus on what matches your actual usage to avoid overspending!

Step 4: How to Find a Reliable Supplier

Not all suppliers accurately label their IP ratings, so it’s crucial to verify their claims. Here’s how.

• Inspect the Build Quality Examine seal tightness and interface design. Reputable manufacturers don’t cut corners on these details. Ask them to provide more details.
• Test a Sample – Perform a simple water resistance test. Ask the supplier to send you the waterproof testing video and test report. You can test the samples in your environment conditions to check the waterproof IP ratings.

Important Note: IP ratings only certify protection against dust and water—not drops, corrosion, or other hazards. For specialized environments, look for additional certifications like MIL-STD or IK ratings.

Waterproof IP Ratings FAQs

Q1: IP68 Means Waterproof Forever, Right?

A: Not really; that’s the misconception! IP68 isn’t a free pass to go scuba diving with your gadget. The rating only tells part of the story—manufacturers set their own depth and time limits. For example, your smartphone might be IP68-rated for 1.5 meters for 30 minutes. An industrial underwater drone could handle 50 meters for 24 hours. If the specs don’t list depth/time, that “IP68” claim is useless.

Q2: Which is better, IP67 or IP68?

A: If your device needs to stay underwater for long periods, go for IP68. Otherwise, IP67 is more cost-effective. If you’re still not sure, please contact us!

Q3: Can IP69K replace IP68?

A: IP69K is primarily protected against high-pressure, high-temperature spray, while IP68 prevents prolonged immersion in water. They are suitable for different applications.

Q4: Why do some devices labeled IP68 still get water damage?

A: Potential reasons:

• Test conditions don’t match: The manufacturer might label it “IP68 (1 meter / 30 minutes),” but you’re using it at 2 meters underwater.
• Seal wear and tear: Over time, rubber seals can deteriorate.
• Physical damage: Dropping or bumping the device can cause the casing to deform.

Q5: Does the IP protection level degrade over time?

A: Yes! Factors that contribute to performance degradation include Seal aging, worn or cracked housings, and extreme temperatures that cause adhesives to fail.