What Is the Full Charge Voltage of a 4.8V NiMH Battery?
A fully charged 4.8V NiMH Battery usually reaches around 5.6V to 6.0V immediately after charging. Because a 4.8V NiMH Battery contains four 1.2V Nickel-Metal Hydride cells connected in series, the voltage temporarily rises above the nominal 4.8V rating during charging before stabilizing after resting.
How Many Cells Are Inside a 4.8V NiMH Battery?
A 4.8V NiMH Battery normally contains four NiMH cells connected in series. Each cell has a nominal voltage of about 1.2V, so 1.2V × 4 cells gives the pack its 4.8V rating. This is why small packs such as a 4.8V 220mAh NiMH Battery, 4.8V 600mAh NiMH Battery, or 4.8V 750mAh NiMH Battery can all share the same voltage rating while offering different runtime capacity.
The important point is that nominal voltage is not the same as full-charge voltage. The 4.8V number describes the normal rated voltage, while the actual voltage can rise higher during charging and then settle after the pack rests.
What Voltage Does a Fully Charged 4.8V NiMH Battery Reach?
A fully charged 4.8V NiMH Battery does not stay at exactly 4.8V. While charging, the pack may rise to around 6.4V–6.6V. Right after you remove it from the charger, a fresh reading is often around 5.6V–6.0V. After resting for a few hours, it usually stabilizes near 5.2V–5.4V.
This behavior applies across many capacities, whether you are checking a 4.8V 1000mAh NiMH Battery, a 4.8V 1500mAh NiMH Battery Pack, or a 4.8V 1600mAh Rechargeable NiMH Battery. Capacity changes runtime, but the four-cell voltage pattern remains similar.
Why Does a 4.8V NiMH Battery Measure Over 5V After Charging?
If your 4.8V NiMH Battery measures over 5V after charging, that is usually normal. The reading is higher because the pack still has temporary surface charge, and the battery chemistry needs time to stabilize. This is why a freshly charged 4.8V 1800mAh NiMH Battery Pack, 4.8V 2200mAh NiMH Battery Pack, or 4.8V 3000mAh NiMH Battery may look “too high” at first but then drop into a normal resting range.
The safer way to judge the pack is not one instant voltage reading. Check whether the pack is hot, whether the charger stopped correctly, and whether the voltage settles after resting. A temporary voltage spike is normal; continuous overheating or never-ending charging is not.
What Is the Resting Voltage of a 4.8V NiMH Battery?
The resting voltage of a fully charged 4.8V NiMH Battery is usually around 5.2V to 5.4V after the pack has been removed from the charger and left with no load for several hours. This is the voltage you should trust more than the instant reading right after charging.
Right after charging, the pack may still carry temporary surface charge, so your meter can show a higher number. Once the battery stabilizes, the no-load voltage gives you a more realistic view of whether the pack is actually full, weak, or starting to lose capacity.
What Is the Peak Charging Voltage of a 4.8V NiMH Battery?
When a 4.8V NiMH Battery is actively charging, the pack voltage can rise to around 6.4V to 6.6V. This higher number usually appears while the charger is still pushing current into the four-cell pack, not after the battery has fully rested.
A proper 4.8V NiMH Battery Charger should not rely on voltage alone. A smarter charger uses delta-V detection, temperature awareness, or timed termination to stop charging before heat and pressure shorten battery life. This is especially important if the pack is used in RC receivers, transmitter packs, emergency devices, or other equipment where stable output matters.
At What Voltage Is a 4.8V NiMH Battery Considered Empty?
A 4.8V NiMH Battery is usually getting low when it falls near 4.4V to 4.8V under light load. Around 4.0V to 4.4V, it is close to empty. If the pack drops into the 3.6V to 4.0V cutoff range, you should recharge it instead of continuing to drain it deeply.
For a dead 4.8V NiMH battery, voltage alone may not tell the whole story. If it drops quickly under load, gets unusually hot while charging, or cannot hold voltage after a full charge, the pack may have aged cells, imbalance, or internal resistance problems.
| State | Pack Voltage | What It Means |
|---|---|---|
| Low Battery | 4.4V–4.8V | The pack is still usable, but runtime is already dropping. |
| Nearly Empty | 4.0V–4.4V | Recharge soon, especially in devices sensitive to voltage drop. |
| Cutoff Range | 3.6V–4.0V | Stop discharging to reduce deep-discharge stress. |
Can You Use a 5V USB Charger With a 4.8V NiMH Battery?
You should not connect a 4.8V NiMH Battery directly to a normal 5V USB power source. USB power only provides voltage; it does not automatically control charging current, detect when the NiMH pack is full, or stop charging safely. For a four-cell pack, current control matters more than simply matching a nearby voltage number.
If you need USB input, use a charger circuit designed for NiMH battery charging. A proper charger limits current, monitors charge behavior, and helps prevent overheating risk. This is especially important for small packs used in RC receiver packs, handheld devices, hobby electronics, and backup modules.
Recommended Charging Current for Different 4.8V NiMH Battery Packs
The right charging current depends on battery capacity. A small 4.8V 220mAh NiMH Battery needs a much lower current than a large 4.8V 5000mAh NiMH Battery. As a practical rule, many NiMH packs are charged around 0.1C to 0.2C for safer standard charging, unless the battery and charger are specifically designed for faster charging.
For replacement packs, do not only look at voltage. Match the capacity, connector, polarity, physical size, and charging method. This matters whether you are replacing a 4.8V 300mAh NiMH RX Battery, a 4.8V AAA 700mAh NiMH Battery Pack, or a higher-capacity pack used for longer runtime.
| Battery Type | Recommended Charging Current | Typical Use Note |
|---|---|---|
| 4.8V 220mAh NiMH Battery | 22mA–44mA | Small backup or compact device pack |
| 4.8V 300mAh NiMH RX Battery | 30mA–60mA | RC receiver pack or hobby control pack |
| 4.8V AAA 700mAh NiMH Battery Pack | 70mA–140mA | AAA-size rechargeable pack |
| 4.8V 1000mAh NiMH Battery | 100mA–200mA | Medium-capacity device pack |
| 4.8V 2000mAh NiMH Transmitter Battery Pack | 200mA–400mA | Transmitter battery pack with longer runtime |
| 4-Cell 4.8V 4Ah NiMH Battery | 400mA–800mA | Higher-capacity rechargeable pack |
| 4.8V 5000mAh NiMH Battery | 500mA–1000mA | Longer runtime pack for heavier duty use |
Common Applications for 4.8V NiMH Battery Packs
A 4.8V NiMH Battery Pack is common in devices that need a simple four-cell rechargeable power source. You will often see it in RC receiver packs, transmitter battery packs, hobby electronics, emergency systems, and compact backup power designs.
For example, a 4.8V 300mAh NiMH RX Battery is usually chosen for lightweight receiver use, while a 4.8V 2000mAh NiMH Transmitter Battery Pack is more suitable when you need longer operating time. The voltage can be the same, but the capacity, size, connector, and discharge demand should match the actual device.
4.8V NiMH Battery Voltage Summary Table
When you check a 4.8V NiMH Battery with a multimeter, the number you see depends on the battery state. A nominal 4.8V pack can read much higher while charging or right after charging, then settle after several hours of resting voltage stabilization.
| State | Total Voltage | Voltage Per Cell | What It Means |
|---|---|---|---|
| Nominal | 4.8V | 1.2V | Rated voltage of a four-cell NiMH pack. |
| Peak Charging | 6.4V–6.6V | 1.6V–1.65V | Possible while the charger is actively charging. |
| Fresh Full | 5.6V–6.0V | 1.4V–1.5V | Common reading immediately after charging. |
| Resting Full | 5.2V–5.4V | 1.3V–1.35V | More reliable full-charge reading after stabilization. |
| Empty | 3.6V–4.0V | 0.9V–1.0V | Recharge soon to avoid deep-discharge stress. |
For everyday checking, the fresh full voltage tells you what the pack looks like right after charging, while the resting full voltage tells you whether the battery has stabilized normally.
FAQ
What is the full charging voltage of a 4.8V NiMH battery?
A fully charged 4.8V NiMH Battery typically measures between 5.6V and 6.0V immediately after charging.
Why does a 4.8V NiMH battery reach over 5V after charging?
This is caused by temporary surface charge and normal charging behavior in Nickel-Metal Hydride batteries.
What is the resting voltage of a 4.8V NiMH battery?
After resting for several hours, most fully charged 4.8V NiMH Battery packs stabilize around 5.2V to 5.4V.
What is the peak charging voltage of a 4.8V NiMH battery?
While actively charging, the voltage can briefly rise to around 6.4V–6.6V before charge termination.
At what voltage is a 4.8V NiMH battery considered dead?
Most 4-cell NiMH battery packs are considered empty around 3.6V–4.0V.
Can I charge a 4.8V NiMH battery with a USB charger?
Only if the charger includes proper NiMH charging control and current regulation.
Why does voltage drop after removing the charger?
The battery loses temporary surface charge and stabilizes to its normal resting voltage.
Is a 4.8V NiMH battery the same as a lithium battery?
No. NiMH and lithium batteries use different charging methods and voltage behavior.