Reforming Batteries With the Help of Implicit and Explicit Consumer Measures

The lifespan or longevity of a (single-use) battery has long been the primary metric of its performance, adopted in the industry, and not least by Duracell. Yet, research and development people in Duracell embarked recently on a search for additional benefits that may be hidden but could be important to consumers. They revealed a dimension of battery performance that made them shift their focus and change their approach to satisfying consumer expectations from their alkaline batteries. Furthermore, they employed a combination of implicit (biometric) and explicit (survey-based) measures of consumer response to the performance of their batteries, which actually led them to turn their attention to the performance of devices powered by batteries.

The Duracell brand (“durable cell”) was founded in 1965; it became an independent company in follow-up from Mallory Company (the battery development and business were started by Samuel Ruben and Philip Rogers Mallory in the 1920s and accelerated in the 1940s). Duracell went through several hands from 1978 (e.g., Kraft) until it was acquired by Gillette in 1996, which was later taken over by Procter and Gamble (P&G) in 2005. Since 2016 Duracell is in ownership of Berkshire Hathaway (cf. Duracell ‘About Us’ [UK], Wikipedia). Ray Iveson, who has led the research initiative and change of approach in Duracell, is VP R&D and Senior Research Fellow in the company. Iveson worked for P&G during the period it owned Duracell, though he was earlier engaged in other business units of P&G (e.g., skincare and haircare). His last assignment at P&G was to the Duracell unit, and he continued with Duracell when it departed from P&G. Iveson’s original vocation is as an engineer (biomedical), but his major specialisation, developed over the years, is in methods and measurements regarding product performance or efficacy, and consumer perceptions.

  • Duracell offers three classes of alkaline batteries: Optimum (200% longevity*), Plus (100% longevity*), and Simply (‘value’ priced)[* evaluated relative to an industry regulated standard].
  • The batteries come in five sizes: AAA, AA, C, D, & 9V. Optimistic projections of sales growth are based on increased use of batteries in many devices, and making these batteries recyclable.
  • A single-use battery is described as a battery that from the moment it is installed in a client-device it lets the device ‘run’ until energy in the battery cell is exhausted (i.e., the battery cannot be recharged and has to be disposed of).
  • Other products of Duracell include: rechargeable batteries and chargers, Smart Power charging and energy management systems, coin and button batteries (Lithium-Ion).
  • Brand competition to Duracell includes: Energizer, Gold Peak (GP), Varta, Toshiba, retail private labels.

The research and development process for upgrading the batteries utitlised three main categories of measures:

  • Explicit consumer feedback (obtained by survey questions and rating scales)
  • Implicit consumer response (eye tracking, pupil size, galvanic skin response)
  • Objective (technical) performance tests on products (batteries)

The family of methods and measures of implicit responses is the latest addition to the research tool box. It is an emerging area of research, based on biometric attributes, that aims to seek and complement information about consumer response (e.g., physiological, neural, and neurophysiological linking the former two domains) that consumers cannot or would not voluntarily disclose. Duracell implemented the technology, devices and analytics for measuring implicit responses offered by iMotions, a research firm specialising in this field.

  • Tracing facial expressions, another methodology offered by iMotion, is also being used by Duracell, as said in interviews by Iveson, but it was not utilised in this particular project.

Duracell together with iMotions have let consumers-participants use devices (e.g., LED flashlight), powered by alkaline batteries, and took explicit measures of their usage experience, as reported by the participants (e.g., performance rating), and implicit measures of (autonomous) responses while a device is being used by participants. Each type of measure of implicit response has a particular purpose, pertaining to a property of human cognition, affect, or behaviour: eye tracking evaluates attention, what consumers are looking at and for how long; pupil size and galvanic skin response can indicate arousal and engagement. A dedicated kind of biosensor is used for each measurement type. Capturing implicit and explicit responses in combination places the consumer at the centre or focus of the development process, that is by ensuring that the consumer-user’s perspective is accounted for and guides the process (“Powering Duracell’s Consumer Insight Advancements“, Nadia Pedersen, iMotions, 15 June 2021). [Note: Measures of facial expressions reflect primarily affective, subconscious responses such as surprise, delight or dismay.]

The duration for which a device (e.g., flashlight, radio set, game console) can continue to ‘run’ on a single-use alkaline battery (longevity) is no doubt an important attribute; it has functional and economic implications for the user. However, the recent research suggested that it is not enough looking at how long the client-device can run on batteries, because what could matter even more to consumers-users is how well the device operates and performs while being powered by the batteries. For instance, the device should run reliably and uninterruptedly (e.g., a stable light beam), at a comfortable or practical level (e.g., light intensity), and that batteries would not cause damage to the device while being in use. The batteries have to support the functionalities and qualities afforded by the device to its users. The research findings advised Duracell’s team a change in approach of shifting the focus from the battery itself, and its longevity, to the perspective of quality of performance of the device it ‘serves’.

Nadia Pedersen (iMotions) points out how Duracell found that the physiological or implicit responses of consumers were not fully revealed by their explicit responses. The more biosensor studies Duracell conducted, surfacing additional aspects of battery performance, “they continued to see how consumers, even if they couldn’t consciously convey it, wanted something different than what the battery industry standards demanded from Duracell (and other battery manufacturers)“. Hence, Pedersen summarises: “Device performance, not battery life, was the priority for consumers“.

Following their initial discoveries with existing batteries, Duracell’s R&D team developed a new set of battery versions that would address the issues raised by the implicit responses of consumers, not fully captured through explicit feedback. Duracell carried-out a series of user tests applying devices with their prototype battery forms, compared with devices run by their older-existing batteries and the batteries of competitors (batteries already in the market) — the devices with batteries were all blind-tested (i.e., the identity of existing and new-reformed Duracell’s batteries were all concealed by removing or covering their labels). Pedersen and Iveson indicate that the new prototype batteries, made to enhance their capabilities in powering client-devices, performed consistently better than incumbent batteries, particularly referring to Duracell’s competition (they are somewhat vague about their own ‘old’ batteries).

A cornerstone in the lessons of Iveson from the research he carried out with his team, as he tells about them in two interviews, regards non-linearity in consumer responses:

Iveson relates to a non-linear relation between changes in levels of physical attributes and the value of change to consumers. This non-linearity can be seen, he notes, in how consumers approach differences between points on a Likert-type rating scale (i.e., for consumers, the difference between 5 and 6 on a rating scale is not necessarily valued the same as a difference between 7 and 8 on a 10-point scale). When we plot consumers’ ratings against physical attributes (‘technical data’) yet also against implicit measures, we would often find that the consumers are non-linear in the way they use these scales. As far as it concerns changes in physical attributes, it implies that we should pay attention to how they are valued by consumers through their explicit ratings as well as by their implicit responses.

Iveson suggests that it is unrealistic to expect a single benefit to be the basis for a product developed for consumers. A company has to identify two to four ‘vectors’ of benefit that will provide 90% of the response sought from the consumers, and identifying those additional benefits is the difficult task. The vector of performance of a device powered by batteries was ignored, according to Iveson, not intentionally due to lack of awareness (Dooley’s podcast). Much of what Iveson talks about concerns issues of psychophysics, such as response to intensity of light emitted by a battery-powered flashlight. Iveson says, for example, that they were surprised by how small differences in a device’s physical attributes (stimuli) consumers could notice (i.e., known as the ‘just noticeable difference’, JND). They concluded that battery longevity adds to quality of device performance as two key benefits to consumers.

As with many research projects for commercial applications, many details about the methodologies and findings are left out because of proprietary interests. In the case of Duracell, we do not know, for instance, what are the linear and non-linear relations obtained between physical (product), physiological (implicit), and mental (explicit) metrics, nor are we told what modifications were actually made to create the prototype batteries. Since non-linearity in human response (e.g., to physical and abstract stimuli {prices}, physiological and mental responses) is actually recognised for many years, it is difficult to evaluate the discovery in this research [consider for example the non-linear value functions of gain and loss in Prospect Theory by Kahneman and Tversky]. The claim Iveson makes about rating scales is interesting because it undermines the assumption that responses (values) are assigned on an interval measurement scale. On the one hand, it sounds as if Duracell could have made their discovery a while ago. On the other hand — which could be significant — relatively new biometric measures of implicit responses appear to provide a critical empirical corroboration that Duracell’s R&D team needed to advance their new concept and approach. Still, a question remains as to what type of human valuations matters more (i.e., has stronger impact on consumer decisions), values reflected from consumers’ implicit neuro-physiological responses or their conscious cognitive responses. The right answer proposed here is that we should consider both, and negotiate between them.

Duracell might apply conjoint (choice) experiments and preference models. It would allow estimating the balance in importance between durability (battery life) and other attributes such as battery integrity, reliability and efficiency (a trade-off which is actually missing from Duracell’s research). Yet, it is true that one needs a prior study to identify and define the relevant attributes in addition to durability or longevity. Furthermore, we may need to ‘twist’ the experiment design in order to present the performance attributes of the battery (focal product) via its impact on performance of the device it powers. The motivation for applying a conjoint methodology is to trace when and where (for what consumers) longevity could be less important than the quality of performance of the device a battery runs.

The batteries of Duracell continue to be classified upon longevity and a price-value proposition on the company’s website, as mentioned above. There is no distinction regarding the ability of batteries to deliver better performance of the battery-powered devices — is it embedded in all alkaline batteries now, or do the marketing people ignore it? An explanation of the newly-added benefit would be welcome. However, in the background on Duracell (‘About-us’), the company states, while including more potential benefits of its batteries: “Duracell has a long history of innovation through continuously developing batteries that are more compact, more powerful, more efficient, and longer lasting than competitor brands” (bold typeface added).

It is largely accepted today that a company cannot develop a product internally and then turn to the marketing and sales people to introduce and promote the new product to consumers in the market; consumers have to be involved and listened to from early stages of the development process through research and collaboration. Iveson strongly acknowledges the importance, actually necessity, of starting with the consumers and engage them through the development process. Taking the proper measurements is based on understanding what consumers desire and do not desire (Quirk’s Q&A). However, one is left in doubt as to whether co-operation exists between the R&D people and the marketing (particularly marketing research) people in Duracell during the R&D process. Iveson comments that people in other functions in the company, such as marketing, take similar approaches nowadays to customer experience (CX) and employ biometric measures (Dooley’s podcast), yet it remains ambiguous to what extent these functions collaborate between them during the R&D project and afterwards (in follow-up on CX).

The research of Iveson and his R&D team at Duracell makes at least two key contributions. Firstly, it reveals a new perspective, a dimension of benefit, that shifts attention from the battery itself to the device the consumer is ultimately using. In other words, it recognises that consumers care about how well a device they are using performs, enabled by the energy power from batteries, in doing a ‘job’ they are tasked with — the device and battery are in it together in allowing the consumer to achieve his or her goal. Secondly, the research principally demonstrates the advantages of combining measures of implicit and explicit consumer responses, and the importance of understanding the relations between them. Moreover, it shows how such research design can help in consumer-driven development of new or upgraded products.

Ron Ventura, Ph.D. (Marketing)