Briggs & Stratton’s Power Swap
By Mike Brezonick15 March 2022
In taking the next step in the evolution of its Vanguard battery systems, Briggs & Stratton decided to think small.
Not small in the sense that the company’s new Vanguard Lithium-Ion 1.5 kWh Swappable Battery Pack is in any way a minor development. The new battery packs, combined with the company’s existing 3.8, 5 and 10 kWh Vanguard Commercial batteries, give the Milwaukee, Wis., power provider as wide a standard product line as any in the industry.
Rather, it’s small in that one of the primary attributes is essentially borrowed from smaller batteries that have long been used in power tools and small outdoor power products such as Briggs & Stratton’s own Snapper Pro 82 V outdoor power products.
“We’re not necessarily reinventing the wheel,” said Dave Frank, global vice president of commercial sales – engines & batteries at Briggs & Stratton. “We took what we’ve done with our Snapper products and what the hand tool guys have been doing for a number of years and are bringing it to larger equipment.
“You can think of this 1.5 kWh battery like being that Snapper battery on steroids. There are tons of power that you can get out of it because it is obviously much bigger. But it’s similar in that it’s maneuverable and easy to swap in and out of a machine.”
First unveiled as a concept late last year, the Swappable Battery Packs target a broad range of construction, agricultural, lawn & garden and industrial applications. The batteries can be taken from one machine to another and can be used in parallel with as many as 10 batteries to meet larger power needs.
The battery packs are similar to the larger Vanguard batteries in that they consist of cell module assemblies incorporating cylindrical cells connected through a wire bonding process that maintains a gap between the cells. “We could probably get 2 kWh in that enclosure if we didn’t care about safety,” Frank said. “We prioritize safety over cell density.
“Knowing how these batteries are going to be used and how they will be moved around and dropped sometimes, we wanted to make sure that each battery – and I mean each single cell – is protected. Each cell is separated from one another so in case there is something like a thermal event, it’s going to be in one cell and it won’t migrate to the rest of the pack.”
Machines using the Swappable Battery Packs will include a Briggs & Stratton-supplied docking assembly that, in combination with a battery management system (BMS) integral to the battery, will enable the battery to be optimized for each application.
“When it gets mounted to a log splitter, it will know what the power characteristics are expected and how we want that battery to perform on that log splitter,” Frank said. “When we put that battery on a concrete saw, there are rpms we want to keep the machine to in order to keep the vibration as low as possible. We can tell that battery to run at that constant speed for that machine.
“The controller that will ultimately tell the electric motor how to run is mounted to the docking station which we provide and we’re able to flash that. Now when you take that battery to a different machine the BMS asks, what are you expecting of me, controller? The controller tells it the characteristics, the battery accepts and then performs however needed for that machine.”
The battery chemistry of the Swappable Battery Packs is essentially the same as the larger batteries, with a different mix of capacities. “In most batteries, you have some cells that are designed for long life,” he said. “They’re like an engine that runs all its life at 2200 rpm and are never asked run harder. Mid-power range cells, which are what we’re using today in the majority of our permanent battery packs, give more of that perfect mixture of long life and performance.
“The cells we’re using in these are really more dedicated to performance. The reason is because we want to make sure that no matter what we ask that battery to do – whether it’s an application that needs a lot of power in a short amount of time or it needs to run over an extended period of time – it has the ability to do that.”
In testing, Frank said Briggs & Stratton saw “applications where the battery life is 15 minutes and applications where the battery lasts seven hours,” making it difficult to predict operating hours or range. “But if you run out of power and you’ve still got work to do, you can just swap one battery out and put another one in,” he said.
The Swappable Battery Packs will be available with two charger options, a 400 W unit that plugs into a standard wall socket and will provide a full charge in four hours. A 1425 W charger, which can also be plugged into a standard wall outlet, can recharge the battery in approximately 1.5 hours. “What’s more impressive,” said Frank of the high-capacity charger, “it’ll get the battery to 80% of a full charge in a little bit less than an hour.”
Along with its targeted machine applications, Frank said the batteries would be especially suitable for the rental industry. “The rental operator could have a number of different electric powered machines, and they wouldn’t all have to have their own integral battery,” he said. “He could just have a bank of batteries that he could pull off the wall and send the customer out the door. Or with a couple of batteries and a charger.
“Now that rental yard has another source of income because now, they can charge for the usage rather than charging them for time. Some customers rent a machine for four hours and will use it nonstop for four hours. Another customer will use it for 45 minutes. They can charge them for the actual usage of the machine.”
The battery packs will ultimately incorporate dual CANJ1939 (29-bit, 500 kbps) networks, enabling communication to and from the machine, as well as to the internet via an IoT device. That connectivity also enables remote monitoring and control of the battery and machine.
The Swappable Battery Packs are designed to withstand machine environments and are fully sealed and able to endure a lot of handling. “We wanted to make sure they’re droppable,” Frank said. “The production samples are going to be made out of a diecast aluminum – we’re leveraging one of our major strengths from Vanguard engines, which is diecasting – and we’ll be adding extra shielding around that to really make sure we’re protecting those batteries.”
The Swappable Battery Packs are expected to begin pre-production around the end of the second quarter of this year, with regular production expected early 2023. The initial units will be built at the company’s Ion Works within the company’s Milwaukee headquarters facility, but Frank noted that Briggs is “making a huge investment” at its Tucker, Ga., plant “where we’ll be able to manufacture these at a high volume to support our customers.”