At the port of Constanța in Romania, technicians unfasten a high‑voltage battery and lower it into a tank. Around them, more than 150 journalists from sixteen European countries watch this 228‑kilogram block face off against the saltwater. Because the image speaks for itself, and Chery knows the public remains wary of batteries in electrified SUVs.
That day, the Chinese automaker staged its new battery, called Guardian, along the shores of the Black Sea. At the center of the demonstration is the pack from the plug‑in hybrid SUV Chery Tiggo 9. This battery, built for CSH technology, delivers 34.46 kWh of capacity and weighs 228 kilograms. It is submerged for 24 hours in a salt solution of 3.5%. Then the SUV strikes a 25‑centimeter concrete obstacle at about 15 km/h. It raises questions about what such a test really says about high‑voltage battery protection.
A battery from the Chery Tiggo 9 submerged 24 hours in saltwater
The technicians begin by laying the Tiggo 9 high‑voltage pack on a bench. This sealed assembly delivers 34.46 kWh and weighs 228 kilograms. They lower it into a tank filled with roughly 4,000 liters of water, stirred with 35 grams of salt per liter. The salt concentration reaches about 3.5%, close to seawater salinity. The battery disappears completely beneath the surface, at a depth of roughly 1.2 meters, and stays there for twenty‑four hours. Safety standards such as GB 38031 or KMVSS typically require immersion of one to two hours. Here, with twenty‑four hours in salty water, Chery clearly pushes the usual regulatory limits beyond the standard test.
When the day is over, the pack is hoisted from the tank. It then passes into the hands of Chery’s team and German engineers from FEV. They search for signs of corrosion, deformation of the enclosure, bulges, or any visible leaks. The high‑ and low‑voltage connectors, as well as the relief valve, are also scrutinized. Measurements show insulation resistance above 500 megaohms between the high‑voltage circuit and the enclosure. That indicates the salty water did not create an electrical leakage path through the housing. A pressurization test of the enclosure reveals an air leak of 8.067 pascal per minute. The internal limit is set at 31 pascal per minute, leaving a comfortable margin for the seal. After reassembling into the SUV, the Tiggo 9 starts normally. No warning messages appear on the instrument panel, and no abnormal heating is detected by the on‑site team. It should be noted that the pack benefits from multi‑layer protection designed to withstand external abuse. Notably, there is a very strong steel undershield on the road side. This sequence is run by the manufacturer itself, in a highly controlled environment, far from the chaos of a real flood.
After the saltwater, the Chery Tiggo 9 tackles a concrete block
Once the immersion test is validated, Chery moves on to a second scenario that speaks to drivers’ everyday experience. The Tiggo 9 is launched at roughly 14 to 15 km/h toward a concrete step standing 25 centimeters tall. The impact with the obstacle is intentional, not something the vehicle tries to avoid. One can imagine a raised curb, a harsh speed bump, or a high parking‑garage step. Under the vehicle, the steel plate and the various protective layers must first absorb the impact. The test then serves to verify on‑the‑ground the much‑advertised multi‑layer structure for the CSH pack.
- the condition of the underbody protection plate and its PVC coating, exposed during the initial impact,
- the battery enclosure’s integrity, looking for cracks, dents, or any visible structural deformation,
- the high‑ and low‑voltage connectors, along with the coolant lines situated very close to the point of impact.
The lower plate shows scratches and some marks on the PVC coating, but the metal framework remains intact. Engineers report no cracks, leaks, or abnormal deformation of the battery housing itself. The electrical connectors and the coolant lines also emerge undamaged after the impact. This matters because those elements can become critical in the event of electrolyte leakage or a temperature spike. No warning light appears on the dashboard, and the SUV continues its test run without any visible symptoms. This is a deliberate, scripted protocol conducted by Chery, with a single car and a single battery configuration. Such a demonstration does not replace independent testing or a real flood or crash scenario. It fits a staged narrative aligned with the brand’s family‑oriented positioning, widely promoted under the slogan For Family. It shows how far automakers are willing to go to prove, with images, the resilience of their batteries.
