# Replacement 3-cell laptop battery BTI L77991-005 for HP 850 G7 / 855 G7 / 850 G8 / ZBook Firefly 15 G8, 11.55V 5850mAh (68Wh), black

**URL:** https://aio.lv/en/product--bti-l77991-005-bti--11672841
**Data updated:** 2026-01-08 10:40 (EET)
**Category:** Portable Device Batteries
**Manufacturer:** BTI
**Manufacturer code:** L77991-005-BTI
**EAN:** 5059902006257
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 152.49 €
**Prices and availability valid until:** 2026-07-22 23:59
**Price without VAT (21%):** 126.02 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--bti-l77991-005-bti--11672841

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 16.07.2026 | free |
| Pickup points | 21.07.2026 | 1.89 EUR |
| Courier delivery to door | 21.07.2026 | 4.99 EUR |

## Summary description

Replacement 3-cell BTI laptop battery compatible with HP models 850 G7, 855 G7, 850 G8 and ZBook Firefly 15 G8. Specifications: Li‑Ion chemistry, 11.55 V nominal voltage, 5850 mAh (68 Wh) capacity, colour black. Replaces OEM part numbers such as 28Y92UC, CC03XL, HSTNN-DB90, L77622-2C1, L77622-2C2, L77991-005. Supplied as a single unit for restoring mobile runtime and replacing worn or failing original battery.

## Long description

BTI replacement 3-cell lithium-ion battery for select HP laptops, compatible with models such as HP 850 G7, 855 G7, 850 G8 and ZBook Firefly 15 G8. This battery replaces OEM part numbers 28Y92UC, CC03XL, HSTNN-DB90, L77622-2C1, L77622-2C2 and L77991-005. It is black, supplied as a single unit, and provides 5850 mAh (68 Wh) capacity at 11.55 V.
Advantages
The BTI replacement battery uses lithium-ion technology to deliver reliable power and maintains compatibility with the listed HP laptop models and OEM part numbers. With a rated capacity of 5850 mAh (68 Wh) and nominal voltage of 11.55 V, it is intended to restore portable operation times comparable to original batteries while fitting the same mounting and connector specifications.
Suitable for
 HP EliteBook/ProBook 850 G7 and 850 G8 series
 HP 855 G7 laptops
 ZBook Firefly 15 G8 mobile workstations
 Replacing OEM batteries with part numbers 28Y92UC, CC03XL, HSTNN-DB90, L77622-2C1, L77622-2C2, L77991-005
Key specifications
 Battery technology: Lithium-Ion (Li-Ion)
 Capacity: 5850 mAh / 68 Wh
 Voltage: 11.55 V
 Cells: 3-cell
 Color: Black
 Units included: 1 pc
How to use
Power down the laptop, disconnect the AC adapter, and remove the bottom cover according to the laptop manufacturer's service instructions. Remove the existing battery by unscrewing and disconnecting its connector, then install the BTI replacement battery in the same orientation and secure it with the original screws. Reattach the cover, reconnect the AC adapter, and charge the battery fully before normal use.
Usage recommendations
Use the replacement battery with compatible HP models only. Follow manufacturer safety guidelines: avoid exposure to heat, puncture, or water, and dispose of the old battery in accordance with local regulations. If uncertain about disassembly, have the battery replaced by a qualified technician.

## Specifications

| Feature | Value |
|---|---|
| Quantity per pack | 1 pc(s) |

### Battery

| Feature | Value |
|---|---|
| Compatible products | COMPAQ |
| Battery technology | Lithium-Ion (Li-Ion) |
| Battery capacity | 5850 mAh |
| Number of battery cells | 3 |
| Battery voltage | 11.55 V |
| Battery capacity | 68 Wh |
| Number of batteries included | 1 pc(s) |
| Product colour | Black |

### Technical details

| Feature | Value |
|---|---|
| Brand compatibility | HP |

## FAQ

### How much does the BTI 3-cell laptop battery L77991-005 for HP 850 G7 cost, and is it available for purchase?

The price is 152.49 € (valid at the time of publication and already includes all taxes). The item is available for order — 6 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 16.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay, Installment. All transactions are 100% secure and encrypted.

### Can BTI 3-cell laptop battery L77991-005 for HP 850 G7 be purchased with a lease?

Yes, the purchase is available both on credit and with an interest-free installment plan. Learn more about installments and credit options: https://aio.lv/en/payment#b3

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All BTI products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized BTI service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

### How can I tell if this product suits my needs?

When making a choice, we recommend paying attention to the key features: compatible products, battery technology, battery capacity, product colour, compatibility with your devices or usage conditions, material quality, functionality, and warranty terms. These characteristics will help you determine how well the model meets your needs.

## Image

https://aio.lv/img/cache/product/11672841/66980734_large.webp