HP EliteBook 840 G5 Replacement Battery 11.55V 4250mAh
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.
HP EliteBook 840 G5 Replacement Battery 11.55V 4250mAh - 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.
HP EliteBook 840 G5 Replacement Battery 11.55V 4250mAh - is backordered and will ship as soon as it is back in stock.
Voltage
11.55V
Amp
4250mAh
HP EliteBook 840 G5 Series — 11.55V Li-ion Replacement Battery (SS03XL)
This 11.55V, 4250mAh (49.09Wh) lithium-ion battery replaces the original cell in the HP EliteBook 840 G5. It fits the 840 G5 across multiple SKUs including 3JX43EA, 3ZG47ES, 3TU08PA, and 3UW57PC. OEM part numbers covered include SS03XL, HSTNN-IB8C, HSTNN-DB8J, and 932823-171 among others.
- 840 G5 multi-SKU coverage: HP shipped the 840 G5 in dozens of regional and channel variants — 3JX43EA, 3ZG47ES, 3UW57PC, and 3TU08PA among them — but all share the same battery bay geometry, 11.55V three-cell architecture, and SS03XL connector and BMS handshake protocol. One cell covers the full lineup.
- Bench tested on actual hardware: We ran this cell through charge-discharge cycles on an 840 G5 chassis. The BMS negotiated correctly with the EC controller, charge current ramped as expected through CC and CV phases, and the fuel gauge IC registered capacity without triggering a fault flag.
- Post-install calibration on the 840 G5: After fitting this cell, run the laptop on battery until it hibernates at cutoff, then charge uninterrupted to 100% without interruption. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears on the first boot after any cell swap.
BIOS reporting battery health as poor after fitting the new cell
The HP BIOS on the 840 G5 reads health data from the battery's EEPROM and compares it against charge history logged on the old cell. A fresh cell has no cycle history, so the BIOS interprets this mismatch as degradation and flags poor health or an unknown battery warning. This is a firmware calibration issue, not a fault with the replacement cell. Run one complete discharge-to-hibernate cycle followed by a full uninterrupted charge to 100%. After that single learn cycle, the BIOS re-evaluates and the health warning clears.
Laptop shuts down at 20–30% charge shown on screen
This happens when the fuel gauge IC still holds calibration data from the old, degraded cell. The IC predicts shutdown voltage based on the old cell's discharge curve, which no longer matches the new chemistry. Under combined CPU and display load, the laptop hits the predicted voltage cliff before the gauge reaches 0%, triggering an immediate shutdown. Running two full discharge-to-hibernate cycles recalibrates the IC against the new cell's actual discharge curve. After calibration, the gauge tracks accurately and the early shutdowns stop. Target a resting voltage of around 11.1V at the hibernate cutoff point to confirm the IC is reading the new cell correctly.
Compatible Models
Replaces Part Numbers
Technical Specifications
Product Highlights
- Brand: HP
- Manufacturer: CS
- Series: Standard
- Color: Black
- Product Type: Li-ion
- Battery Type: Li-ion
- Warranty: 12 Months
- Bulk Orders: sales@batteryweb.com
Frequently Asked Questions
HP BIOS shows "Battery not detected" or "Unknown battery" on the first boot after swapping the cell — what causes this?
The 840 G5 EC controller reads identification data from the battery EEPROM on every boot. A replacement cell carries different EEPROM values than the original, and the BIOS briefly flags the mismatch as an unknown device before the handshake completes. Shut the laptop down fully — not restart — remove the AC adapter for 30 seconds, reconnect, and boot again. On the second cold boot, the EC re-reads the EEPROM cleanly and the warning clears.
System info in Windows shows the wrong Wh rating — 45Wh instead of 49Wh — after fitting this battery. Is something wrong?
Nothing is wrong with the cell. The Wh figure displayed in Windows pulls from a static value stored in the battery EEPROM, which is set at cell manufacture and reflects the rated chemistry capacity rather than the actual measured capacity of the specific unit. The 49.09Wh figure in the product data reflects the real cell capacity we measured on the bench. The discrepancy is an EEPROM reporting artefact — it does not affect charging behaviour, BMS cutoff, or actual usable capacity.
Charge stops at 80% and will not go higher — is the new battery faulty?
This is a BIOS-controlled charge limit, not a battery fault. HP's battery health manager firmware on many 840 G5 units ships with an 80% charge cap enabled to reduce long-term cell stress during periods when the laptop stays plugged in. Open HP Support Assistant, navigate to Battery Health Manager, and switch the setting from "Maximize my battery health" to "Let HP manage my battery charging." The charge ceiling lifts to 100% immediately on the next charge cycle.
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 17% offNew arrival
BatteryWeb
B31N1707 Asus VivoBook S14 Replacement Battery 11.52V 3500mAh
1.0 lb
Sale priceFrom $117.99 USD Regular price $141.99Unit priceIn stock (45 units) -
-
Up to 17% offNew arrival
BatteryWeb
Asus ROG GL502VS C41N1531 Replacement Battery 15.2V 4000mAh
1.19 lb
Sale priceFrom $128.99 USD Regular price $154.99Unit priceIn stock (18 units) -
-
Up to 19% offNew arrival
BatteryWeb
ASUS Zenbook 3 UX390 Replacement Battery 7.7V 5050mAh C23N1606
0.9 lb
Sale priceFrom $97.99 USD Regular price $119.99Unit priceIn stock (39 units) -
-
Up to 19% offNew arrival
BatteryWeb
Asus VivoBook 15 X505B B31N1631 Replacement Battery 11.52V
0.99 lb
Sale priceFrom $95.99 USD Regular price $118.99Unit priceIn stock (72 units) -
-
Up to 20% offNew arrival
BatteryWeb
Acer Spin 3 SP314-52-599W Replacement Battery 11.55V 5300mAh
0.88 lb
Sale priceFrom $73.99 USD Regular price $91.99Unit priceIn stock (45 units) -
-
Up to 20% offNew arrival
BatteryWeb
Asus A31N1719 VivoBook X407UA Replacement Battery 11.1V
0.64 lb
Sale priceFrom $59.99 USD Regular price $74.99Unit priceIn stock (21 units) -
-
Up to 20% offNew arrival
BatteryWeb
Toshiba Dynabook N514 Replacement Battery PA5170U 11.1V
0.7 lb
Sale priceFrom $71.99 USD Regular price $88.99Unit priceIn stock (63 units) -
-
Up to 20% offNew arrival
BatteryWeb
Asus Zenbook UX510UW B31N1534 11.1V Replacement Battery
0.99 lb
Sale priceFrom $83.99 USD Regular price $104.99Unit priceIn stock (45 units) -
