Daramic SLI Separators

Daramic Battery Separators

Car starters
Hand crank — turn the key — press the "Start" button...

The way to start a car has become easier over time thanks to the combination of the battery powered electric starter. Since then, the battery has moved from an aid to start, to include powering the headlamps, radio and other conveniences that make today's cars more comfortable and safer.

With the advancement of vehicle electrification, including start-stop technology new challenges have fallen on lead acid batteries. Now more than ever they are required to deliver greater power in an efficient and sustainable manner. This has led to a step change in flooded lead acid design from standard starting, lighting, and ignition (SLI) batteries to as Enhanced Flooded Battery (EFB).

EFB batteries are an enhanced version of standard wet-flooded technology. The primary benefits of this technology are improved charge acceptance and greater cyclic durability when operating in a reduced state of charge (typical of Stop Start applications).

For over 90 years, Daramic has led the way in developing new and innovative technology for the automotive lead acid battery market. With headquarters in Charlotte, North Carolina, USA—Daramic today supplies high performance polyethylene and phenolic resin battery separators to the lead acid battery industry.

Battery cross-section
Fun Fact: Tesla and other BEVs require a lead acid battery for starting!

Regardless of the type of battery, or type of vehicle, a common component across all is the battery separator.

Car showing battery under hood
What is a Separator?

A battery separator performs two primary functions. First, it provides mechanical strength between electrodes preventing shorts within the battery. Second, its microporousity allows the flow of ions to pass during charge and discharge cycles. In addition to these important functions, Daramic separators provide low electrical resistance, oxidation resistance, while reducing the potential for water loss, grid corrosion and acid stratification making them the preferred solutions to meet customers' needs.

To achieve this, the separator must be porous and wettable so acid can permeate through it, as the battery charges or discharges. It should not impede or restrict the flow of ions between the anode and cathode. The separator must be manufactured from materials resistant to the acidic and oxidative environment within the battery. It must also be strong enough to withstand the assembly operations and perform its functions as a mechanical spacer under thermal and vibration conditions during the life of the battery. In addition, the separator should be designed to displace as little acid as possible since this is the fuel or reserve capacity for the battery itself.

Daramic Separators:

SeparatorsDaramic offers a broad lineup of automotive separators used in original equipment manufacturer and aftermarket lead-acid batteries. A key component of an automobile, the lead-acid battery is supported by a separator that meets the electrification needs of starting, lighting, and ignition and start-stop vehicles.

SLI separators
Daramic® HP

Daramic® HP is a high-performance polyethylene battery separator designed for starting, lighting and ignition (SLI) and enhanced flooded lead acid battery applications. Daramic HP is specially formulated to deliver excellent puncture and oxidation resistance, while also providing lower electrical resistance.

DuraLife logoDuraLife® is a new, high performance polyethylene battery separator specially designed for starting, lighting and ignition (SLI) and enhanced flooded lead-acid batteries. DuraLife's patented design significantly improves battery life with lower grid diffusion and improves efficiency and yield during battery assembly.

Daramic® EFS for Start-Stop Vehicles
Daramic's new lineup of separators are specifically designed to support start-stop vehicle battery work requirements, enabling battery manufacturers and automotive OEMs to deliver reliable battery power for users of start-stop vehicles.

As a global leader, Daramic operates 10 manufacturing facilities. Each facility is strategically located, ensuring continuity of supply and fast delivery.
Map of manufacturing facilities
Daramic is committed to delivering unsurpassed expertise in advanced separator technology. Our Center of Innovation in Owensboro, Kentucky, USA is the central hub for our scientists, industry experts and service technicians.

For more information, visit the Daramic website.