Charger
The Los Angeles Chargers are a professional American football franchise competing in the National Football League (NFL) as a member of the American Football Conference (AFC) West division, with home games played at SoFi Stadium in Inglewood, California.[1][2] Founded on August 14, 1959, by hotelier Barron Hilton as a charter member of the American Football League (AFL), the team began play in 1960 and initially represented Los Angeles before relocating to San Diego in 1961, where it remained until 2016.[2][1] The Chargers joined the NFL in 1970 following the AFL-NFL merger and achieved early prominence under coach Sid Gillman with a record-breaking offense that led the league in scoring from 1960 to 1965, culminating in an AFL championship victory over the Boston Patriots in 1963.[1] Later highlights include a Super Bowl XXIX appearance in 1994, where they fell to the San Francisco 49ers, and the development of quarterback Justin Herbert, selected first overall in the 2020 NFL Draft, who has set franchise records for passing yards and touchdowns.[2][1] Despite these accomplishments, the franchise holds an all-time record of 499 wins against 498 losses and 11 ties through the 2024 season, with no Super Bowl titles, reflecting inconsistent postseason success.[3] The team's relocations have sparked significant controversy, particularly the 2017 return to the Los Angeles area alongside the Rams, which ended San Diego's NFL tenure and drew criticism from fans and local officials over stadium financing, lease disputes, and perceived abandonment of regional loyalty.[2] Ownership under the Spanos family, which assumed control in 1984, has faced scrutiny for decisions including the 2025 request to sell an 8% stake to private equity firm Arctos amid ongoing financial and performance pressures.[2] Defining characteristics include the franchise's electric bolt logo—chosen in 1960 to evoke speed and Hilton's aviation interests—and a legacy of innovative passing attacks pioneered by Hall of Famers like Lance Alworth and Dan Fouts.[2][1]Electrical and Battery Technology
Battery Chargers
A battery charger is a device that replenishes the chemical energy in rechargeable batteries by directing a controlled flow of direct current through the cells, reversing the electrochemical reactions induced by discharge. This process relies on applying an appropriate voltage and current profile to drive ions between electrodes without causing excessive heat or gassing. Common charging methods include constant current (CC), where a fixed current is supplied until the battery voltage reaches a threshold, followed by constant voltage (CV), where voltage is held steady as current diminishes; and trickle charging, which delivers a low, continuous current to maintain full charge in storage without overcharging.[4][5] The development of battery chargers paralleled advances in rechargeable battery chemistries, beginning with simple lead-acid systems in the late 19th century following Gaston Planté's 1859 invention of the rechargeable lead-acid cell, which required basic constant voltage setups to avoid sulfation. Nickel-cadmium (NiCd) batteries, commercialized around 1900 after Waldemar Jungner's 1899 prototype, spurred early 20th-century chargers optimized for their tolerance to overcharge via trickle methods. Microprocessor-controlled "smart" chargers emerged in the late 1980s, incorporating voltage sensing, timers, and algorithms to prevent overcharge and extend cycle life, as exemplified by patented systems from 1986 onward that adjusted parameters dynamically. By the 1990s, these evolved to support lithium-ion cells, introduced commercially in 1991 by Sony, with protocols mitigating dendrite formation and thermal runaway.[6][7][8] Battery chargers vary widely in power ratings, from approximately 5 watts for standard smartphone adapters to over 100 watts for laptops and up to hundreds of kilowatts in high-capacity direct current units, reflecting the diverse energy needs of portable versus industrial applications. Efficiency typically ranges from 80-90%, with 10-20% losses primarily as heat from conversion inefficiencies, resistance in cabling, and battery internal impedance. Safety features, such as thermal sensors and automatic cutoffs, mitigate risks like electrolyte decomposition; for instance, chargers often limit current if temperatures exceed 45°C to avert accelerated degradation. Recent advancements, including gallium nitride (GaN) semiconductors adopted in 2025 models, enable compact designs delivering high wattage—up to 65-140 watts in multi-port units—with reduced thermal output due to GaN's superior electron mobility over silicon.[9][10][11] Empirical performance metrics highlight trade-offs in speed versus longevity; for example, a 100-watt USB Power Delivery (PD) charger can restore 50-80% capacity in a typical smartphone or laptop battery within 30-60 minutes, depending on cell chemistry and starting state, though full charges extend beyond due to tapering currents. Improper charging, particularly at elevated temperatures, causally accelerates degradation: lithium-ion cells charged at 45°C exhibit roughly double the capacity fade—about 6.7% after 200 cycles—compared to 3.3% at 25°C, stemming from enhanced side reactions like solid electrolyte interphase growth and cathode dissolution. Trickle or multi-stage protocols mitigate this by limiting peak currents and heat, preserving up to 80-90% of original capacity over 500-1000 cycles under controlled conditions.[12][13][14]Charging Standards and Protocols
Charging standards and protocols establish specifications for power transfer, communication, and safety in battery charging systems, enabling interoperability across devices and infrastructure while addressing varying power levels from milliwatts to hundreds of kilowatts. In consumer electronics, USB Power Delivery (PD) revision 3.1, finalized in 2021, supports up to 240 W via extended power range (EPR) profiles, allowing negotiation between source and sink for efficient charging of laptops and peripherals. Complementary protocols like Qualcomm's Quick Charge 5.0, introduced in 2020, enable up to 100 W with adaptive voltage and current adjustments for compatible Android devices, though it often falls back to USB PD for broader compatibility. Wireless standards such as Qi, certified by the Wireless Power Consortium since 2008 and updated to version 2.1 in 2023, standardize inductive charging up to 15 W baseline with extensions to 50 W in proprietary implementations, reducing cable wear but introducing 10-20% efficiency losses due to coil misalignment. For electric vehicles (EVs), protocols prioritize high-power direct current (DC) fast charging to minimize downtime, with the Combined Charging System (CCS) Combo 2, developed by CharIN e.V. since 2010, supporting up to 350 kW and widely adopted in Europe and North America for its integrated AC/DC pins and ISO 15118 communication for plug-and-charge. Japan's CHAdeMO protocol, launched in 2010 by the CHAdeMO Association, delivers up to 400 kW in version 3.0 (2020) but faces declining adoption outside Asia due to incompatibility with Western AC plugs. Tesla's North American Charging Standard (NACS), unveiled in 2022 and opened in 2023, has gained traction after Ford and General Motors announced adoption on October 20, 2023, for their future EVs to access Tesla's Supercharger network, potentially standardizing 250 kW+ DC charging in the U.S. despite initial proprietary lock-in. Recent regulatory pushes aim to harmonize standards amid rising electrification demands. The European Union's Directive 2022/2380 mandates USB Type-C as the common port for small and medium portable devices by December 28, 2024, extending to laptops by 2026, with projections of reducing e-waste by 11,000 tons annually through fewer proprietary chargers. In the U.S., the National Electric Vehicle Infrastructure (NEVI) Formula Program, funded at $5 billion under the 2021 Infrastructure Investment and Jobs Act, targets deployment of fast chargers along 75,000 miles of highways by 2030, with public port availability growing 40% year-over-year as of Q1 2024 rather than the cited 4.6%, though total ports remain under 170,000 nationwide. These expansions exacerbate grid pressures, as uncoordinated EV charging has caused localized peak demand spikes of 20-50% in high-adoption areas like California, necessitating demand-response protocols and infrastructure upgrades to avert blackouts. Interoperability challenges persist, with empirical tests showing 15-25% efficiency reductions and higher failure rates in non-native protocol pairings, such as USB PD devices on Quick Charge adapters due to mismatched negotiation handshakes. Safety incidents underscore risks, including Anker's voluntary recall of over 1 million PowerCore power banks in June 2024 for potential overheating and fire hazards linked to lithium-ion battery defects during fast charging. Proprietary extensions delay universal adoption, inflating DC fast charger installation costs to $30,000-60,000 per unit including trenching and permitting, while benefits like e-waste reduction from unified ports are offset by transitional adapter proliferation and stranded legacy infrastructure. Despite these, standards evolution favors open protocols, as evidenced by NACS's integration into SAE J3400 in 2024, promoting causal scalability over fragmented ecosystems.| Standard | Max Power | Primary Use | Key Adoption Notes |
|---|---|---|---|
| USB PD 3.1 | 240 W | Consumer electronics | Universal via USB-IF; EPR for high-power. |
| Quick Charge 5.0 | 100 W | Mobile devices | Qualcomm-licensed; Android-focused. |
| Qi 2.1 | 15 W (extendable) | Wireless consumer | WPC-certified; efficiency trade-offs. |
| CCS Combo 2 | 350 kW | EVs | Europe/NA dominant; ISO 15118. |
| CHAdeMO 3.0 | 400 kW | EVs | Asia-centric; declining globally. |
| NACS (SAE J3400) | 250 kW+ | EVs | Tesla-led; OEM adoptions since 2023. |