During our Bosch training last weekend (yes, it was a Sunday!) we learnt that the Bosch GBH 180-LI might bog down under heavy load if it's used with a Bosch 18V lithium battery pack lower than 3.0Ah. This is primarily due to the heavier current draw from the GBH 180-LI's brushed motor which is some 30% less efficient than their brushless (EC motor) cousins.

To prove the point, the brushless rotary hammer such as the Bosch GBH 18V-26 is not affected by this shortcoming even when used under heavy load with a battery pack half the size such as the Bosch 18V 1.5Ah lithium battery pack. 

The simple workaround for the GBH 180-LI is to use 3.0Ah or higher battery packs or purchase the GBH 180-LI and GBH 18V-26 combo and only use the GBH 18V-26 for the heavy duty stuff (which is what the GBH 18V-26 was intended to do all along). To Bosch's credit, the GBH 180-LI kit ship with two batteries with a minimum rating of 3.0Ah.

We'd advise customers to purchase the combo kits whenever possible as the battery packs and the charger themselves are not cheap - which is also why it's a great package when paired with the Bosch GLI 180-LI Solo or the Bosch GOP18 V-EC Solo multi-cutter combo package. The GLI 180-LI is compatible with either the Bosch 18V or the older 14.4V packs.