A 7.4V (2s) LiPo battery can perfectly replace a 7.2V (6-cell) NiMH battery. This is because the fully charged voltage of a 6-cell NiMH battery is 8.4V, which is the same as the fully charged voltage of a 2s LiPo battery. Therefore, there will be no over-voltage that could negatively affect the power system of your RC car.
But what impact does replacing a 7.2V NiMH battery with a 7.4V LiPo battery have on your RC car? And what are the differences between NiMH and LiPo batteries? Let’s take a closer look and analyze these aspects in detail.
| Battery | 2S Lipo | 6 Cell NIMH |
| Minimum Voltage | 6.4V | 5.4V |
| Nominal Voltage | 7.4V | 7.2V |
| Fully Charged Voltage | 8.4V | 8.4V |
Operating Power
In practical discharge scenarios, the discharge voltage of a 2s LiPo battery is consistently higher than that of a 6-cell NiMH battery. Additionally, due to the higher discharge current of LiPo batteries, the effect is increased operating power for your RC car. Therefore, if you want to boost your RC car’s speed, replacing a 7.2V 6-cell NiMH battery with a 7.4V 2s LiPo battery is a straightforward upgrade.
As shown in the picture, this Gens ace 5000mah 2s 7.4V 60C LiPo Battery runs at 37Wh; in addition, another Zeee 3600mah 7.2V NiMH Battery runs at only 25.92Wh.
Run Time
LiPo batteries have a higher energy density compared to NiMH batteries. As a result, within the same size constraints, a 2s LiPo battery offers greater capacity than a 6-cell NiMH battery, thereby extending the run time of your RC car.
Charging Time
Most mainstream RC LiPo batteries support fast charging from 1C to 5C, while NiMH batteries require a longer charging.
Battery Lifespan
LiPo batteries can last over 500 cycles, whereas NiMH batteries typically last around 350. However, misuse such as overcharging and over-discharging can shorten the lifespan of LiPo batteries.
Safety and Environmental Impact
NiMH batteries are generally safer than LiPo batteries, which can swell and pose a fire hazard if misused. Additionally, NiMH batteries do not contain heavy metals, resulting in less environmental pollution. Therefore, NiMH batteries are a good entry-level choice for those new to the RC hobby world.
