Symbol MC9090 3.6V 20mAh Ni-MH CMOS Backup Battery 3/V15H
Check that your old battery model number and device model to match our description. This makes sure they work together.
We ship your order same day if you buy it before 4 PM EST.
Symbol MC9090 3.6V 20mAh Ni-MH CMOS Backup Battery 3/V15H - is backordered and will ship as soon as it is back in stock.
Let customers speak for us
Send Your Battery Photo
Expert Technician Help
Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.
POST YOUR BATTERY IMAGE
Product & Solutions Expert
✉ sales@batteryweb.com
Battery Care Tips
Battery Care Tips
🔹 Getting Started
Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.
🔹 Keep It Healthy
Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.
Delivery and Shipping
Delivery and Shipping
🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.
Disclaimer
Disclaimer
⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.
🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.
Symbol MC9090 3.6V 20mAh Ni-MH CMOS Backup Battery 3/V15H - is backordered and will ship as soon as it is back in stock.
Voltage
3.6V
Amp
20mAh
Symbol MC9090 Series — 3.6V Ni-MH CMOS Backup Battery (3/V15H)
This is a 3.6V, 20mAh Ni-MH CMOS backup battery for the Symbol MC9090 family of rugged mobile computers, including the MC9090-G, MC9090-K, and MC9090-S variants. It powers the real-time clock and SRAM when the main battery is removed or fully drained. Without it, the device loses its clock, network credentials, and scanner configuration every time main power is interrupted.
- MC9090 series compatibility: The MC9090-G, -K, and -S variants all share the same RTC circuit and CMOS backup architecture, drawing from the same voltage rail and using the same connector footprint. One part covers the entire platform.
- Bench tested on actual hardware: We ran this cell through a full main-power removal cycle on an MC9090-G unit. The BMS held clock and SRAM retention without reset, and voltage stayed above the 2.8V minimum retention threshold throughout the test window.
- RTC reset after swap: The CMOS cell powers the RTC circuit directly. Any interruption during replacement — even a few seconds — resets the clock to its default value. After installing this cell, go into the MC9090 device settings and manually set the correct date and time before returning the unit to service.
Clock resetting to a default date after every main battery swap on the MC9090
The MC9090 RTC circuit runs off the CMOS backup cell continuously. When that cell drops below approximately 2.8V, it can no longer sustain the RTC register values during main power removal. The clock resets to the factory default date each time. A depleted cell measures below 3.0V at rest and will not recover — it must be replaced. This cell ships at full rated voltage and restores RTC retention immediately on installation.
MC9090 losing Wi-Fi profiles and scanner settings every time the main battery is pulled
The MC9090 stores network credentials and scanner configuration in SRAM, which is backed by the CMOS cell — not flash memory. Once the backup cell is depleted, all SRAM contents are lost the moment main power is removed. This is different from a clock reset: the device boots clean with no profiles, no paired devices, and no scanner parameters. Replacing the CMOS cell stops the data loss; reconfigure the device once after the swap and the settings will persist through future battery changes.
Compatible Models
Replaces Part Numbers
Technical Specifications
Product Highlights
- Brand: Symbol
- Manufacturer: CS
- Series: Standard
- Color: Green
- Product Type: Ni-MH
- Battery Type: Ni-MH
- Warranty: 12 Months
- Bulk Orders: sales@batteryweb.com
Frequently Asked Questions
My MC9090 keeps showing the wrong date and time after I swap the main battery — why does it keep resetting?
The RTC on the MC9090 is powered by the CMOS backup cell, not the main battery. When that cell drops below 2.8V, it can no longer hold the clock register during a main power swap, so the device reverts to its factory default date every time. The main battery being fine is irrelevant — the backup cell is a separate circuit. Replace the CMOS cell (3/V15H) and manually set the correct date and time immediately after installation.
My MC9090 boots with a CMOS checksum error and all settings are gone — is the motherboard dead?
A CMOS checksum error means the backup cell is fully depleted and the SRAM lost integrity — the device recalculates the checksum on boot, finds a mismatch, and flags it. The motherboard is almost certainly fine. Replace the 3/V15H backup cell, let the unit boot fully, then re-enter your network credentials and scanner configuration. The error clears itself once the CMOS cell is providing stable voltage above 2.8V.
I just installed a new CMOS cell and the MC9090 still says the battery is low — is the new cell faulty?
Ni-MH cells ship at storage voltage, which can read lower than the operating target immediately out of packaging. The cell needs to be seated in-circuit for a short period before voltage stabilises at its rated level. Check the cell contacts on the motherboard — oxidised or bent spring contacts from the old cell are the most common reason a new cell appears not to register. Clean the contacts with isopropyl alcohol, reseat the cell firmly, and recheck voltage; it should read at or above 3.0V once the circuit is live.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Related Products
Engineered for Performance. Built to Last.
Check out our top-rated selection of reliable products built to last. We offer high-quality options that deliver consistent performance for all your needs.
-
Up to 18% offNew arrival
BatteryWeb
VeriFone NURIT 8320 CMOS Backup Battery 3V 250mAh Lithium
0.12 lb
Sale priceFrom $26.99 USD Regular price $32.99Unit priceIn stock (159 units) -
-
Up to 17% offNew arrival
BatteryWeb
Dell Latitude E4200 CMOS Replacement Battery 3V 200mAh
0.06 lb
Sale priceFrom $25.99 USD Regular price $30.99Unit priceIn stock (99 units) -
-
Up to 21% offNew arrival
BatteryWeb
Symbol WT4000 CMOS Backup Battery 2.4V Ni-MH 20mAh
0.12 lb
Sale priceFrom $22.99 USD Regular price $28.99Unit priceIn stock (156 units) -
-
Up to 21% offNew arrival
BatteryWeb
Intermec CN2 CMOS Replacement Battery 3.6V 20mAh Ni-MH
0.06 lb
Sale priceFrom $23.99 USD Regular price $29.99Unit priceIn stock (45 units) -
-
Up to 18% offNew arrival
BatteryWeb
Apple MacBook Pro 15" CMOS Replacement Battery 922-7913 3V
0.06 lb
Sale priceFrom $24.99 USD Regular price $29.99Unit priceIn stock (69 units) -
-
Up to 17% offNew arrival
BatteryWeb
HP ENVY X2 11 CMOS Replacement Battery 3V 150mAh 1126.12
0.06 lb
Sale priceFrom $25.99 USD Regular price $30.99Unit priceIn stock (168 units) -
-
Up to 17% offNew arrival
BatteryWeb
Lenovo ThinkPad Tablet 2 3679-10.1 CMOS Battery 3V 75mAh
0.06 lb
Sale priceFrom $25.99 USD Regular price $30.99Unit priceIn stock (87 units) -
-
Up to 17% offNew arrival
BatteryWeb
HP Presario 300 CMOS Battery 468824-001 3V 75mAh
0.06 lb
Sale priceFrom $25.99 USD Regular price $30.99Unit priceIn stock (93 units) -
