Complex sentence: Lithium batteries marked as "High-voltage" compatible are safe to operate at 4.35V, never overcharge a standard LiPo battery to above 4.2V or damage and/or fire may occur.
Split into simpler sentences: Lithium batteries marked as "High-voltage" compatible are safe to operate at 4.35V. Never overcharge a standard LiPo battery to above 4.2V or damage and/or fire may occur.