Together, they arrived at a solution that aims to present the charity "as both a compassionate caregiver and a leading authority in animal welfare", based around a "family" of hand-drawn logos of different breeds of cats and dogs.
One of the biggest changes is the loss of the "dogs and cats home" from the charity's name. This is replaced with the tagline, "here for every dog and cat".
Pentagram partners Marina Willer and Naresh Ramchandani did this in a bid to "strike out" against the negative connotations associated with the charity sector, including shock tactics and overly emotive language.
"The word 'home' infers a permanent dwelling for Battersea's animals, and could also be understood to mean one location, despite Battersea operating across three sites," explained Pentagram.
Instead, the charity wants to emphasise its commitment towards every dog and cat, which is demonstrated through the imagery of five dogs and five cats, as well as retention of the charity's signature blue colour.
"The abstract illustrations are designed to subtly communicate Battersea's story; they appeal to people's compassion and humanity, without victimising or stigmatising the animals," said Pentagram.
"While the characters are devoid of facial features, they remain expressive and retain a strong sense of individuality," continued the agency. "They celebrate the diverse range of personalities found among Battersea’s dogs and cats, while emphasising the human intervention required to make them whole."
For the text, the designers used a Franklin Gothic typeface, which they chose for its visual "authority".
Pentagram wanted the branding to have the flexibility to adapt to the charity's various fundraising initiatives. Their Muddy Dog challenge, for instance, includes a playful bespoke typeface named Battersea Paws.
The team also commissioned a new series of photographs to reflect the brand's new identity.
Pentagram, one of the world's largest graphics and branding agencies, wasset up in London in 1972 and now has offices across the globe. Recent projects include a visual identity for last year's London Design Festival and branding for an organisation set up to lobby the US government on "tampon tax".
This project marks the first rebrand of Battersea's brand identity since 2005, when it incorporated "cats" into its name and logo.
"From our own research we know that, whilst many people have heard of our charity, they often have an out-of-date perception of us, and what we do," Battersea told Dezeen.
"Like most animal-rescue charities, we're aware that the way people are finding and buying pets is changing and, as increasingly people choose to go online to find their next pet, we need to stand out and communicate effectively in a digital world," it added.
"We are fully committed to our vision and mission to improve the lives of unwanted dogs and cats, and in order to achieve this we have to ensure that Battersea is easily recognisable and relevant to the widest possible audience," said Battersea.