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Li 2 CoSiO 4 has the potential for use as a high safety, high energy-density cathode material for lithium-ion batteries but suffers from bad electrochemical performance. Herein, we demonstrate a profound study on the effects of carbon coating and Al-doping on the electrochemistry of Li 2 CoSiO 4 synthesized by a two-step method. The synthesized 4 at% Al-doped Li 2 CoSiO 4 /C allows two lithium removals between 2.5 and 4.6 V, showing a first charge and discharge capacity of 331 and 140 mA h g -1 , respectively, and a high capacity retention in cycling with no voltage degradation. The relationship between the improved performance and the supporting structural characteristics was studied by galvanostatic charge/discharge measurements and electrochemical impedance spectroscopy, coupled with material characterizations. This work demonstrates that electrical conductivity plays a central role in controlling the electrochemical performance of the modified Li 2 CoSiO 4 . Both the reversibility of delithiation and the irreversible capacity loss are strongly dependent on the electrical condition of the particles, which can be modified by Al-doping and carbon coating. The characteristics of carbon layers are analyzed because of their importance in improving the electrical properties and achieving a solution to the challenges with Li 2 CoSiO 4 . We that show Li 2 CoSiO 4 could have unique electrochemical characteristics that satisfy all the requirements of high safety, high energy density, and high compatibility with the current organic electrolytes if appropriately modified., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objective: To summarize the reason and treatment of redo surgery in Hirschsprung disease for postoperative distension and constipation., Methods: From January to December 2014, 35 patients with constipation and distention after pull-through done elsewhere were referred to our institution. The reasons procedures and outcomes of redo surgery were a retrospectively analyzed., Results: The indication of reoperation in 21 cases was pathological problems, including residual aganglionosis, retained transition zone bowel, and in 13 cases was anatomical problems, including retained dilated segment, obstructive Soave cuff. One case had both pathological and anatomical problems. Among them, 5 cases belonged to total colonic aganglionosis. All the cases received conservative treatment for about 6 months before reoperation. Five cases had enterostomy before redo pull through surgery. Thirty cases underwent Soave surgery with or without laparoscopy or laparotomy. Twenty-six cases underwent transabdominal Soave surgery, 3 cases transanal Soave surgery, 1 case transanal Soave surgery with laparoscopy. Other surgery included Ikeda surgery, excision of diaphragm or scar, and anoplasty. Postoperative complications were found in 3 patients. One had rectovesical fistula and was cured after operation. Two cases had anastomotic leakage and then underwent diverting ileostomy. Thirty-three cases had a mean follow-up of 59 months. During the follow-up, 32 cases had no distension and constipation. Two cases presented occasional dirty pants, 2 cases frequent soiling, 1 case daily soiling., Conclusions: Reasons of distension and constipation in Hirschsprung's disease after surgery are pathological and anatomical problems. Operation procedure is chosen based on reasons. Transabdominal Soave surgery is safe and effective.