This stunned Ning Shu. She covered her flushed cheeks with slender fingers as she sat there at a loss.
"Huh? What happened to them?"
"Could Lu Zhe have hit the class president? I heard a 'slap' sound just now."
"No way. Lu Zhe is such a gentleman, how could he hit a girl? Besides, it didn't sound like it!"
"Everyone's attention is on Ice Sis!"
"Class president, what's going on?"
"A m-mosquito..." Ning Shu stammered, her face red.
On Lu Zhe's side, he was rummaging through Ning Shu's shoulder bag, and sure enough, found her phone!
Along with the charger, it was wrapped tightly in a plastic bag. Despite all the jostling, not a drop of water had leaked in!
There was another bag with several broken phones.
Ning Shu's phone was the only one that remained undamaged. The only issue was that it had run out of battery.
He opened it and examined it carefully. Ning Shu's phone was brand new, a certain model of a popular brand, with a cute rabbit ear phone case and a frosted film for protection.
Girls just loved these flashy accessories, but they did protect the phone from any damage.
"Class president, when did you buy this phone?"
"Last week..."
"Don't joke around. Last week, we were already making pottery!"
"Oh, right, wrong. It was... the week before the plane crash!"
"So it's a new phone!"
Ning Shu took a deep breath and walked over. "What are you trying to do?"
Lu Zhe thought for a moment. "I want to charge your phone and check the information inside."
Upon hearing they could charge the phone, several of the girls crowded around curiously.
Lin Qianqian said, "But what can we use to charge it? We don't even have a socket..."
Tang Xiaoguo's eyes lit up. "I get it!"
It was rare for Xiaoguo to understand something, so Jiang Yao quickly asked, "What method?"
"Lightning!"
Tang Xiaoguo said excitedly, "Use lightning! Lu Zhe, we take a bamboo pole, attach the positive and negative terminals, then stick it outside the cave..."
Lu Zhe nodded. "I'm really busy now. whoever is free, help tie this crazy girl up so she doesn't get herself killed!"
"Haha!" Jiang Yao laughed out loud as she grabbed Tang Xiaoguo.
Tang Xiaoguo's face turned red. "I was just guessing randomly, I wouldn't really do that!"
"Don't we still have a lot of lemons left?"
Lin Qianqian held them up. "They're all here!"
Ning Shu murmured, "A fruit battery?"
Jiang Yao said, "Lu Zhe, I think a lemon battery is theoretically feasible, but not very practical. I've seen a lot of online influencers try similar experiments. Some succeeded, some failed."
In fact, Lu Zhe didn't know if it would work either!
But it was worth a try. What if it succeeded?
"You need to crush the lemons into pulp using a mortar and pestle, the finer the better. Then squeeze all the juice into a can."
"You don't use the whole lemon?"
"For this experiment, electrons need to flow freely between the positive and negative terminals without resistance from the electrolyte solution. Many online videos overlook this point. Using a whole lemon with the sections separated by membranes causes internal resistance, preventing electron flow and causing failure. The successful videos likely pierced a lemon section to allow juice to seep through, enabling flow. But that would still produce very little power."
"Are you sure you're an arts student?"
"It's middle school knowledge!"
"Oh right, I returned all my textbooks to the teachers already."
Next was finding metal wires! Copper and zinc!
Lu Zhe rummaged through Shen Bing's suitcase and pulled out a small bundle of colorful wires.
They had found various discarded wires on the beach before, but since they had no use for them, he had tied them together.
Lu Zhe checked - most were copper.
But copper alone wasn't enough. He still needed zinc.
Zinc metal was hard to find, so he would substitute with aluminum from cans.
Aluminum cans!
He scraped off the oxidized outer layer, then cut thin strips with a knife and twisted them into aluminum wire. These were tied to the opposite ends of the copper wire on the charger.
The copper was coiled into a mosquito coil shape on its end.
The aluminum was a large sheet made by flattening aluminum can bodies.
With the battery ready, both electrodes were inserted into the lemon juice electrolyte.
But...it failed!
The phone showed no reaction at all!
The girls were visibly disappointed.
It looked like he would have to try that after all.
Lu Zhe decided to give it a shot!
He removed the electrodes, then cut the charger cable with his paratrooper knife.
"Why did you break it..."
"Chargers have protective circuits to prevent damage from overvoltage and shorten battery life from undervoltage."
"Oh right, Australia's voltage is similar to China's, we'd still need a converter."
"So we have to take a risk and charge directly at low voltage, bypassing the charging head! Once we find a better charging method, we can reconnect it properly."
Lu Zhe burned away the cable's rubber insulation with fire, exposing the metal wires. He then connected them directly to the copper and aluminum wires.
Try again!
And at that moment, a miracle happened!
On Ning Shu's screen showing 0% battery with a purple water droplet, more purple droplets surged up from below to merge with the one on top!
Five cartoon words appeared at the top of the screen: "Charging..."
At the same time, Lu Zhe heard another "ding" in his mind as his Innate Talent gained +3 Potential Points for creating a basic galvanic cell.
"Wow!"
In that instant, the girls couldn't help crying out in delight, nearly grabbing each other's hands to dance joyously!
"Can we play Glory of Kings on it after charging?"
"You can't connect to the Internet, what's the point?"
"Doesn't it have an offline version? I've seen the class president play. Luban is so annoying to fight!"
"Can we borrow the class president's phone to read novels now? There's probably a lot saved."
"Are there indecent videos and stuff saved too? We can watch together!"
"Nowadays everything needs memberships. Who keeps videos on their phone unless..."
Lu Zhe said solemnly, "I'm telling everyone now. No playing on the phone after it's charged. The class president has important pregnancy info saved. It's extremely valuable to us right now!"
Hearing Lu Zhe say that, the girls obediently nodded.
After two full hours of charging and nearly emptying the entire bag of lemons, there was only 10% battery.
But that was enough to turn it on.
With grave heart, Ning Shu long pressed the power button!
The screen lit up, followed by the boot animation.
The sight was enough to bring tears of joy.
Taking the phone, the first thing Lu Zhe did was adjust the brightness to minimum and force close all background apps to conserve battery as much as possible.
"Where is it, class president?"
Ning Shu flipped through and handed it over. "Here."
"The Great Tang's Peerless Lady Official...
Cannon Fodder Reborn: Ultimate Revenge...
Boss, I meant the reference materials, not novels."
"Oh, sorry!" Ning Shu patted her forehead and quickly searched again.
Finally, Lu Zhe saw what he was looking for.
"Practical Obstetrics And Gynecology...
Human Birth History...
Prenatal Yoga...
Pelvic Surgery And Episiotomy Techniques...
Obstetrics Case Studies...
Reproductive Endocrinology...
Prenatal Nutrition...
Maternal And Infant Care..."
Scrolling further down, there were still 6-7 pages of relevant documents.
Lu Zhe was amazed. "Reading through all these books on this deserted island, we can probably all switch majors and open an obstetrics hospital after getting home."