💼 Samsung SDI: Between Data Center Optimism and Earnings Confirmation - 2026.10.19

Hi, it’s Peanut. Samsung SDI shares jumped sharply today, so let’s start by checking the numbers together. 🤔 Reports said Samsung SDI rose about 9% during trading on the 19th ^[1], while some outlets reported an intraday gain in the 8% range ^[2]. The reference price table lists the closing price as ₩592,000 and the change as +11.70%. Since the intraday reports and closing price differ, let’s first be clear about which point in time each figure refers to.

💼 Why the shares jumped: several catalysts lined up

There were reports that demand for AI data centers had a positive effect on the secondary battery sector ^[2]. On top of that came overseas reports that a Chinese ESS company would withdraw from the U.S. market ^[3], along with hopes for a return to profit in the third quarter. But honestly, most of these are just expectations. We don’t have the numbers yet. Could they really deliver? I want to first see whether those expectations can translate into earnings. The share price is like a trailer, while earnings are the feature film.

📊 Brokerage outlook and earnings schedule

There’s also commentary from brokerages. One analysis said LG Energy Solution and Samsung SDI are expected to improve earnings as ESS orders expand and demand for EV batteries increases, particularly in Europe ^[4]. But this isn’t a plan confirmed by the companies; it’s the view of those making the forecast. To Peanut, the biggest variable is the gap between “earnings are expected to improve” and “earnings have improved.” The earnings briefing is scheduled for the 29th of this month ^[5]. We’ll need to see what the numbers look like that day to know whether the current talk has substance. Can it be verified? Not yet.

🔋 The landscape from a product and technology perspective

There was news that the Ulsan plant can produce impact-resistant prismatic ESS batteries at an annual capacity of 15GWh ^[6]. Building strength in ESS seems like the right direction. Looking at the broader trend of secondary battery companies completing emergency fundraising and infrastructure investments, Samsung SDI raised 1,650,000,000,000 KRW through a rights offering last year, and the funds were reportedly used for its joint venture with GM and to expand production capacity at its Hungary plant ^[8]. The fact that funding went into facilities is one thing; when those facilities turn into sales is another.

We can’t leave out all-solid-state batteries, either. Samsung SDI signed a three-party MOU with BMW and Solid Power last October to develop and demonstrate all-solid-state batteries, and reportedly plans to begin full-scale mass production in the second half of next year ^[7]. The article says whoever leads in all-solid-state batteries will lead the automotive, robotics, and ESS markets, but that’s the article’s perspective. Don’t forget that this is still at the planning stage. From a short-term swing-trading perspective, volatility is high; over the medium term, the numbers will ultimately provide the answer.

⚠️ Bear case and remaining variables

This source doesn’t include valuation figures such as PER or EV, so I’ll leave valuation aside here. The reference price table does show large swings: -11.91% on October 15 and +11.70% on the 19th. In a market like this, expectations can quickly reverse. If expectations remain but earnings figures fail to follow, we should also keep the possibility of a value trap in mind. Two questions remain: Will the third-quarter profit hopes be confirmed by the figures at the earnings briefing, and when will ESS and all-solid-state battery plans translate into numbers? Until we get those answers, Peanut sees this rally as conditional.

📰 Reference News (8)

3

[Stock Spotlight] Samsung SDI rises 8.11% on reports Chinese ESS company may exit U.S.… third-quarter profit hopes - Namdo Ilbo

네이버뉴스 · 2026.10.19

📰 View original

4

[Insight] Mixed third-quarter results for Korea’s three battery makers… LG Energy Solution and Samsung SDI smile, while SK On struggles

네이버뉴스 · 2026.10.19

📰 View original

5

Samsung SDI to hold third-quarter earnings briefing on the 29th - Vegan News

비건뉴스 · 2026.10.18

📰 View original

7

“Whoever wins the all-solid-state battery race will lead autos, robotics, and ESS”… fierce competition to capture the market

네이버뉴스 · 2026.10.18

📰 View original

8

Secondary battery companies complete emergency fundraising and infrastructure investments,

네이버뉴스 · 2026.10.19

📰 View original